Web/JavaScript/Reference/Global objects/String

The String object is used to represent and manipulate a sequence of characters.

Description

Strings are useful for holding data that can be represented in text form. Some of the most-used operations on strings are to check their length, to build and concatenate them using the + and += string operators, checking for the existence or location of substrings with the indexOf() method, or extracting substrings with the substring() method.

Creating strings

Strings can be created as primitives, from string literals, or as objects, using the String() constructor:

const string1 = "A string primitive";
const string2 = 'Also a string primitive';
const string3 = `Yet another string primitive`;

const string4 = new String("A String object");

String primitives and string objects can be used interchangeably in most situations. See "String primitives and String objects" below.

String literals can be specified using single or double quotes, which are treated identically, or using the backtick character `. This last form specifies a template literal: with this form you can interpolate expressions.

Character access

There are two ways to access an individual character in a string. The first is the charAt() method:

return 'cat'.charAt(1) // returns "a"

The other way (introduced in ECMAScript 5) is to treat the string as an array-like object, where individual characters correspond to a numerical index:

return 'cat'[1] // returns "a"

When using bracket notation for character access, attempting to delete or assign a value to these properties will not succeed. The properties involved are neither writable nor configurable. (See Object.defineProperty() for more information.)

Comparing strings

In C, the strcmp() function is used for comparing strings. In JavaScript, you just use the less-than and greater-than operators:

let a = 'a'
let b = 'b'
if (a < b) { // true
  console.log(a + ' is less than ' + b)
} else if (a > b) {
  console.log(a + ' is greater than ' + b)
} else {
  console.log(a + ' and ' + b + ' are equal.')
}

A similar result can be achieved using the localeCompare() method inherited by String instances.

Note that a == b compares the strings in a and b for being equal in the usual case-sensitive way. If you wish to compare without regard to upper or lower case characters, use a function similar to this:

function isEqual(str1, str2)
{
    return str1.toUpperCase() === str2.toUpperCase()
} // isEqual

Upper case is used instead of lower case in this function, due to problems with certain UTF-8 character conversions.

String primitives and String objects

Note that JavaScript distinguishes between String objects and primitive string values. (The same is true of Boolean and Numbers.)

String literals (denoted by double or single quotes) and strings returned from String calls in a non-constructor context (that is, called without using the new keyword) are primitive strings. JavaScript automatically converts primitives to String objects, so that it's possible to use String object methods for primitive strings. In contexts where a method is to be invoked on a primitive string or a property lookup occurs, JavaScript will automatically wrap the string primitive and call the method or perform the property lookup.

let s_prim = 'foo'
let s_obj = new String(s_prim)

console.log(typeof s_prim) // Logs "string"
console.log(typeof s_obj)  // Logs "object"

String primitives and String objects also give different results when using eval(). Primitives passed to eval are treated as source code; String objects are treated as all other objects are, by returning the object. For example:

let s1 = '2 + 2'              // creates a string primitive
let s2 = new String('2 + 2')  // creates a String object
console.log(eval(s1))         // returns the number 4
console.log(eval(s2))         // returns the string "2 + 2"

For these reasons, the code may break when it encounters String objects when it expects a primitive string instead, although generally, authors need not worry about the distinction.

A String object can always be converted to its primitive counterpart with the valueOf() method.

console.log(eval(s2.valueOf()))  // returns the number 4

Escape notation

Special characters can be encoded using escape notation:

Code	Output
`\XXX` (where `XXX` is 1–3 octal digits; range of `0`–`377`)	ISO-8859-1 character / Unicode code point between `U+0000` and `U+00FF`
`\'`	single quote
`\"`	double quote
`\\`	backslash
`\n`	new line
`\r`	carriage return
`\v`	vertical tab
`\t`	tab
`\b`	backspace
`\f`	form feed
`\uXXXX` (where `XXXX` is 4 hex digits; range of `0x0000`–`0xFFFF`)	UTF-16 code unit / Unicode code point between `U+0000` and `U+FFFF`
`\u{X}` ... `\u{XXXXXX}` (where `X…XXXXXX` is 1–6 hex digits; range of `0x0`–`0x10FFFF`)	UTF-32 code unit / Unicode code point between `U+0000` and `U+10FFFF`
`\xXX` (where `XX` is 2 hex digits; range of `0x00`–`0xFF`)	ISO-8859-1 character / Unicode code point between `U+0000` and `U+00FF`

Long literal strings

Sometimes, your code will include strings which are very long. Rather than having lines that go on endlessly, or wrap at the whim of your editor, you may wish to specifically break the string into multiple lines in the source code without affecting the actual string contents. There are two ways you can do this.

Method 1

You can use the + operator to append multiple strings together, like this:

let longString = "This is a very long string which needs " +
                 "to wrap across multiple lines because " +
                 "otherwise my code is unreadable."

Method 2

You can use the backslash character (\) at the end of each line to indicate that the string will continue on the next line. Make sure there is no space or any other character after the backslash (except for a line break), or as an indent; otherwise it will not work.

That form looks like this:

let longString = "This is a very long string which needs \
to wrap across multiple lines because \
otherwise my code is unreadable."

Both of the above methods result in identical strings.

Constructor

String(): Creates a new String object. It performs type conversion when called as a function, rather than as a constructor, which is usually more useful.

Static methods

String.fromCharCode(num1 [, ...[, numN)]]: Returns a string created by using the specified sequence of Unicode values.
String.fromCodePoint(num1 [, ...[, numN): Returns a string created by using the specified sequence of code points.
String.raw(): Returns a string created from a raw template string.

Instance properties

String.prototype.length: Reflects the length of the string. Read-only.

Instance methods

String.prototype.charAt(index)

Returns the character (exactly one UTF-16 code unit) at the specified index.

String.prototype.charCodeAt(index)

Returns a number that is the UTF-16 code unit value at the given index.

String.prototype.codePointAt(pos)

Returns a nonnegative integer Number that is the code point value of the UTF-16 encoded code point starting at the specified pos.

String.prototype.concat(str [, ...strN ])

Combines the text of two (or more) strings and returns a new string.

String.prototype.includes(searchString [, position])

Determines whether the calling string contains searchString.

String.prototype.endsWith(searchString [, length])

Determines whether a string ends with the characters of the string searchString.

String.prototype.indexOf(searchValue [, fromIndex])

Returns the index within the calling String object of the first occurrence of searchValue, or -1 if not found.

String.prototype.lastIndexOf(searchValue [, fromIndex])

Returns the index within the calling String object of the last occurrence of searchValue, or -1 if not found.

String.prototype.localeCompare(compareString [, locales [, options)]]

Returns a number indicating whether the reference string compareString comes before, after, or is equivalent to the given string in sort order.

String.prototype.match(regexp)

Used to match regular expression regexp against a string.

String.prototype.matchAll(regexp)

Returns an iterator of all regexp's matches.

String.prototype.normalize([form])

Returns the Unicode Normalization Form of the calling string value.

String.prototype.padEnd(targetLength [, padString])

Pads the current string from the end with a given string and returns a new string of the length targetLength.

String.prototype.padStart(targetLength [, padString])

Pads the current string from the start with a given string and returns a new string of the length targetLength.

String.prototype.repeat(count)

Returns a string consisting of the elements of the object repeated count times.

String.prototype.replace(searchFor, replaceWith)

Used to replace occurrences of searchFor using replaceWith. searchFor may be a string or Regular Expression, and replaceWith may be a string or function.

String.prototype.replaceAll(searchFor, replaceWith)

Used to replace all occurrences of searchFor using replaceWith. searchFor may be a string or Regular Expression, and replaceWith may be a string or function.

String.prototype.search(regexp)

Search for a match between a regular expression regexp and the calling string.

String.prototype.slice(beginIndex[, endIndex])

Extracts a section of a string and returns a new string.

String.prototype.split([sep [, limit] ])

Returns an array of strings populated by splitting the calling string at occurences of the substring sep.

String.prototype.startsWith(searchString [, length])

Determines whether the calling string begins with the characters of string searchString.

String.prototype.substr()

Returns the characters in a string beginning at the specified location through the specified number of characters.

String.prototype.substring(indexStart [, indexEnd])

Returns a new string containing characters of the calling string from (or between) the specified index (or indeces).

String.prototype.toLocaleLowerCase( [locale, ...locales])

The characters within a string are converted to lowercase while respecting the current locale.

For most languages, this will return the same as toLowerCase().

String.prototype.toLocaleUpperCase( [locale, ...locales])

The characters within a string are converted to uppercase while respecting the current locale.

For most languages, this will return the same as toUpperCase().

String.prototype.toLowerCase()

Returns the calling string value converted to lowercase.

String.prototype.toString()

Returns a string representing the specified object. Overrides the Object.prototype.toString() method.

String.prototype.toUpperCase()

Returns the calling string value converted to uppercase.

String.prototype.trim()

Trims whitespace from the beginning and end of the string. Part of the ECMAScript 5 standard.

String.prototype.trimStart()

Trims whitespace from the beginning of the string.

String.prototype.trimEnd()

Trims whitespace from the end of the string.

String.prototype.valueOf()

Returns the primitive value of the specified object. Overrides the Object.prototype.valueOf() method.

String.prototype.@@iterator()

Returns a new Iterator object that iterates over the code points of a String value, returning each code point as a String value.

HTML wrapper methods

Deprecated. Avoid these methods.

They are of limited use, as they provide only a subset of the available HTML tags and attributes.

String.prototype.anchor(): <a name="name"> (hypertext target)
String.prototype.big(): <big>
String.prototype.blink(): <blink>
String.prototype.bold(): 
String.prototype.fixed(): <tt>
String.prototype.fontcolor(): 
String.prototype.fontsize(): 
String.prototype.italics(): 
String.prototype.link(): <a href="url"> (link to URL)
String.prototype.small(): 
String.prototype.strike(): <strike>
String.prototype.sub(): 
String.prototype.sup():

Examples

String conversion

It's possible to use String as a more reliable toString() alternative, as it works when used on null, undefined, and on symbols. For example:

let outputStrings = []
for (let i = 0, n = inputValues.length; i < n; ++i) {
  outputStrings.push(String(inputValues[i]));
}

Specifications

Specification
ECMAScript (ECMA-262)The definition of 'String' in that specification.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet	Node.js
`String`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`String()` constructor	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`anchor` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1 Notes' Full support 1 Notes' Notes' Starting with version 17, the quotation mark (") is replaced by its HTML reference character (`"`) in strings supplied for the `name` parameter.	IE No support No	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`big` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`blink` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`bold` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`charAt`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`charCodeAt`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 4	Opera Full support 4	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`codePointAt`	Chrome Full support 41	Edge Full support 12	Firefox Full support 29	IE No support No	Opera Full support 28	Safari Full support 10	WebView Android Full support 41	Chrome Android Full support 41	Firefox Android Full support 29	Opera Android Full support 28	Safari iOS Full support 10	Samsung Internet Android Full support 4.0	nodejs Full support 4.0.0 Full support 4.0.0 Full support 0.12 Disabled' Disabled' From version 0.12: this feature is behind the `--harmony` runtime flag.
`concat`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 4	Opera Full support 4	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`endsWith`	Chrome Full support 41	Edge Full support 12	Firefox Full support 17	IE No support No	Opera Full support 28	Safari Full support 9	WebView Android Full support ≤37	Chrome Android Full support 36	Firefox Android Full support 17	Opera Android Full support 24	Safari iOS Full support 9	Samsung Internet Android Full support 3.0	nodejs Full support 4.0.0 Full support 4.0.0 Full support 0.12 Disabled' Disabled' From version 0.12: this feature is behind the `--harmony` runtime flag.
`fixed` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`fontcolor` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`fontsize` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`fromCharCode`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 4	Opera Full support 4	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`fromCodePoint`	Chrome Full support 41	Edge Full support 12	Firefox Full support 29	IE No support No	Opera Full support 28	Safari Full support 10	WebView Android Full support 41	Chrome Android Full support 41	Firefox Android Full support 29	Opera Android Full support 28	Safari iOS Full support 10	Samsung Internet Android Full support 4.0	nodejs Full support 4.0.0 Full support 4.0.0 Full support 0.12 Disabled' Disabled' From version 0.12: this feature is behind the `--harmony` runtime flag.
`includes`	Chrome Full support 41	Edge Full support 12	Firefox Full support 40 Full support 40 No support 18 — 48 Alternate Name' Alternate Name' Uses the non-standard name: `contains`	IE No support No	Opera Full support 28	Safari Full support 9	WebView Android Full support 41	Chrome Android Full support 41	Firefox Android Full support 40 Full support 40 No support 18 — 48 Alternate Name' Alternate Name' Uses the non-standard name: `contains`	Opera Android Full support 28	Safari iOS Full support 9	Samsung Internet Android Full support 4.0	nodejs Full support 4.0.0
`indexOf`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`italics` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`lastIndexOf`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 6	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`length`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`link` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`localeCompare`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 5.5	Opera Full support 7	Safari Full support 3	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`match`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 4	Opera Full support 4	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`matchAll`	Chrome Full support 73	Edge Full support 79	Firefox Full support 67	IE No support No	Opera Full support 60	Safari Full support 13	WebView Android Full support 73	Chrome Android Full support 73	Firefox Android Full support 67	Opera Android Full support 52	Safari iOS Full support 13	Samsung Internet Android No support No	nodejs Full support 12.0.0
`normalize`	Chrome Full support 34	Edge Full support 12	Firefox Full support 31	IE No support No	Opera Full support 21	Safari Full support 10	WebView Android No support No	Chrome Android Full support 34	Firefox Android Full support 31	Opera Android Full support 21	Safari iOS Full support 10	Samsung Internet Android Full support 2.0	nodejs Full support 0.12
`padEnd`	Chrome Full support 57	Edge Full support 15	Firefox Full support 48	IE No support No	Opera Full support 44	Safari Full support 10	WebView Android Full support 57	Chrome Android Full support 57	Firefox Android Full support 48	Opera Android Full support 43	Safari iOS Full support 10	Samsung Internet Android Full support 7.0	nodejs Full support 8.0.0 Full support 8.0.0 Full support 7.0.0 Disabled' Disabled' From version 7.0.0: this feature is behind the `--harmony` runtime flag.
`padStart`	Chrome Full support 57	Edge Full support 15	Firefox Full support 48	IE No support No	Opera Full support 44	Safari Full support 10	WebView Android Full support 57	Chrome Android Full support 57	Firefox Android Full support 48	Opera Android Full support 43	Safari iOS Full support 10	Samsung Internet Android Full support 7.0	nodejs Full support 8.0.0 Full support 8.0.0 Full support 7.0.0 Disabled' Disabled' From version 7.0.0: this feature is behind the `--harmony` runtime flag.
`raw`	Chrome Full support 41	Edge Full support 12	Firefox Full support 34	IE No support No	Opera No support No	Safari Full support 10	WebView Android No support No	Chrome Android Full support 41	Firefox Android Full support 34	Opera Android No support No	Safari iOS Full support 10	Samsung Internet Android Full support 4.0	nodejs Full support 4.0.0
`repeat`	Chrome Full support 41	Edge Full support 12	Firefox Full support 24	IE No support No	Opera Full support 28	Safari Full support 9	WebView Android No support No	Chrome Android Full support 36	Firefox Android Full support 24	Opera Android Full support 28	Safari iOS Full support 9	Samsung Internet Android Full support 3.0	nodejs Full support 4.0.0 Full support 4.0.0 Full support 0.12 Disabled' Disabled' From version 0.12: this feature is behind the `--harmony` runtime flag.
`replace`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 4	Opera Full support 4	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`replaceAll`	Chrome Full support 85	Edge Full support 85	Firefox Full support 77	IE No support No	Opera Full support 71	Safari Full support 13.1	WebView Android Full support 85	Chrome Android Full support 85	Firefox Android Full support 79	Opera Android Full support 60	Safari iOS Full support 13.4	Samsung Internet Android No support No	nodejs No support No
`search`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 4	Opera Full support 4	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`slice`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 4	Opera Full support 4	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`small` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`split`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 4	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`startsWith`	Chrome Full support 41	Edge Full support 12	Firefox Full support 17	IE No support No	Opera Full support 28	Safari Full support 9	WebView Android Full support ≤37	Chrome Android Full support 36	Firefox Android Full support 17	Opera Android Full support 24	Safari iOS Full support 9	Samsung Internet Android Full support 3.0	nodejs Full support 4.0.0 Full support 4.0.0 Full support 0.12 Disabled' Disabled' From version 0.12: this feature is behind the `--harmony` runtime flag.
`strike` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`sub` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`substr` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 4	Opera Full support 4	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`substring`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`sup` Deprecated'	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`toLocaleLowerCase`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 5.5	Opera Full support 4	Safari Full support 1.3	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`toLocaleUpperCase`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 5.5	Opera Full support 4	Safari Full support 1.3	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`toLowerCase`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`toSource` Non-standard'	Chrome No support No	Edge No support No	Firefox No support 1 — 74 Notes' No support 1 — 74 Notes' Notes' Starting in Firefox 74, `toSource()` is no longer available for use by web content. It is still allowed for internal and privileged code.	IE No support No	Opera No support No	Safari No support No	WebView Android No support No	Chrome Android No support No	Firefox Android Full support 4	Opera Android No support No	Safari iOS No support No	Samsung Internet Android No support No	nodejs No support No
`toString`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`toUpperCase`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 3	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`trim`	Chrome Full support 4	Edge Full support 12	Firefox Full support 3.5	IE Full support 9	Opera Full support 10.5	Safari Full support 5	WebView Android Full support ≤37	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 11	Safari iOS Full support 5	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`trimEnd`	Chrome Full support 66 Full support 66 Full support 4 Alternate Name' Alternate Name' Uses the non-standard name: `trimRight`	Edge Full support 12 Alternate Name' Full support 12 Alternate Name' Alternate Name' Uses the non-standard name: `trimRight`	Firefox Full support 61 Full support 61 Full support 3.5 Alternate Name' Alternate Name' Uses the non-standard name: `trimRight`	IE No support No	Opera Full support 53 Full support 53 Full support 15 Alternate Name' Alternate Name' Uses the non-standard name: `trimRight`	Safari Full support 12	WebView Android Full support 66 Full support 66 Full support ≤37 Alternate Name' Alternate Name' Uses the non-standard name: `trimRight`	Chrome Android Full support 66 Full support 66 Full support 18 Alternate Name' Alternate Name' Uses the non-standard name: `trimRight`	Firefox Android Full support 61 Full support 61 Full support 4 Alternate Name' Alternate Name' Uses the non-standard name: `trimRight`	Opera Android Full support 47 Full support 47 Full support 14 Alternate Name' Alternate Name' Uses the non-standard name: `trimRight`	Safari iOS Full support 12	Samsung Internet Android Full support 9.0 Full support 9.0 Full support 1.0 Alternate Name' Alternate Name' Uses the non-standard name: `trimRight`	nodejs Full support 10.0.0 Full support 10.0.0 Full support 0.12 Alternate Name' Alternate Name' Uses the non-standard name: `trimRight`
`trimStart`	Chrome Full support 66 Full support 66 Full support 4 Alternate Name' Alternate Name' Uses the non-standard name: `trimLeft`	Edge Full support 12 Alternate Name' Full support 12 Alternate Name' Alternate Name' Uses the non-standard name: `trimLeft`	Firefox Full support 61 Full support 61 Full support 3.5 Alternate Name' Alternate Name' Uses the non-standard name: `trimLeft`	IE No support No	Opera Full support 53 Full support 53 Full support 15 Alternate Name' Alternate Name' Uses the non-standard name: `trimLeft`	Safari Full support 12	WebView Android Full support 66 Full support 66 Full support ≤37 Alternate Name' Alternate Name' Uses the non-standard name: `trimLeft`	Chrome Android Full support 66 Full support 66 Full support 18 Alternate Name' Alternate Name' Uses the non-standard name: `trimLeft`	Firefox Android Full support 61 Full support 61 Full support 4 Alternate Name' Alternate Name' Uses the non-standard name: `trimLeft`	Opera Android Full support 47 Full support 47 Full support 14 Alternate Name' Alternate Name' Uses the non-standard name: `trimLeft`	Safari iOS Full support 12	Samsung Internet Android Full support 9.0 Full support 9.0 Full support 1.0 Alternate Name' Alternate Name' Uses the non-standard name: `trimLeft`	nodejs Full support 10.0.0 Full support 10.0.0 Full support 0.12 Alternate Name' Alternate Name' Uses the non-standard name: `trimLeft`
Unicode code point escapes \u{xxxxxx}	Chrome Full support 1	Edge Full support 12	Firefox Full support 40	IE Full support 4	Opera Full support 4	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 40	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`valueOf`	Chrome Full support 1	Edge Full support 12	Firefox Full support 1	IE Full support 4	Opera Full support 3	Safari Full support 1	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 10.1	Safari iOS Full support 1	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100
`@@iterator`	Chrome Full support 38	Edge Full support 12	Firefox Full support 36 Full support 36 No support 27 — 36 Notes' Alternate Name' Notes' A placeholder property named `@@iterator` is used. Alternate Name' Uses the non-standard name: `@@iterator` No support 17 — 27 Notes' Alternate Name' Notes' A placeholder property named `iterator` is used. Alternate Name' Uses the non-standard name: `iterator`	IE No support No	Opera Full support 25	Safari Full support 9	WebView Android Full support 38	Chrome Android Full support 38	Firefox Android Full support 36 Full support 36 No support 27 — 36 Notes' Alternate Name' Notes' A placeholder property named `@@iterator` is used. Alternate Name' Uses the non-standard name: `@@iterator` No support 17 — 27 Notes' Alternate Name' Notes' A placeholder property named `iterator` is used. Alternate Name' Uses the non-standard name: `iterator`	Opera Android Full support 25	Safari iOS Full support 9	Samsung Internet Android Full support 3.0	nodejs Full support 0.12

Legend

Full support: Full support
No support: No support
Non-standard. Expect poor cross-browser support.': Non-standard. Expect poor cross-browser support.
Deprecated. Not for use in new websites.': Deprecated. Not for use in new websites.
See implementation notes.': See implementation notes.
User must explicitly enable this feature.': User must explicitly enable this feature.
Uses a non-standard name.': Uses a non-standard name.