Web/CSS/border-top-left-radius

The border-top-left-radius CSS property rounds the top-left corner of an element by specifying the radius (or the radius of the semi-major and semi-minor axes) of the ellipse defining the curvature of the corner.

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

The rounding can be a circle or an ellipse, or if one of the value is 0,no rounding is done and the corner is square.

[[File:../../../../../media.prod.mdn.mozit.cloud/attachments/2012/07/09/3634/bec082e0ec8dfcee0683ffe0bc7d9cd8/border-radius.png|class=default internal|border-radius.png]]

A background, being an image or a color, is clipped at the border, even a rounded one; the exact location of the clipping is defined by the value of the background-clip property.

Note: If the value of this property is not set in a border-radius shorthand property that is applied to the element after the border-top-left-radius CSS property, the value of this property is then reset to its initial value by the shorthand property.

Syntax

/* the corner is a circle */
/* border-top-left-radius: radius */
border-top-left-radius: 3px;

/* the corner is an ellipse */
/* border-top-left-radius: horizontal vertical */
border-top-left-radius: 0.5em 1em;

border-top-left-radius: inherit;

With one value:

• the value is a <length> or a <percentage> denoting the radius of the circle to use for the border in that corner.

With two values:

• the first value is a <length> or a <percentage> denoting the horizontal semi-major axis of the ellipse to use for the border in that corner.
• the second value is a <length> or a <percentage> denoting the vertical semi-major axis of the ellipse to use for the border in that corner.

Values

<length-percentage>

Denotes the size of the circle radius or the semi-major and semi-minor axes of the ellipse. As absolute length it can be expressed in any unit allowed by the CSS <length> data type. Percentages for the horizontal axis refer to the width of the box, percentages for the vertical axis refer to the height of the box. Negative values are invalid.

Formal definition

Initial value	0
Applies to	all elements; but User Agents are not required to apply to table and inline-table elements when border-collapse is collapse. The behavior on internal table elements is undefined for the moment.. It also applies to ::first-letter.
Inherited	no
Percentages	refer to the corresponding dimension of the border box
Computed value	two absolute <length>s or <percentage>s
Animation type	a length, percentage or calc();

Formal syntax

<length-percentage>{1,2}where <length-percentage> = <length> | <percentage>

Examples

Examples of different border-top-left-radius values

Live example	Code
	An arc of ellipse is used as the border div { border-top-left-radius: 40px 40px; }
	An arc of ellipse is used as the border div { border-top-left-radius: 40px 20px; }
	The box is a square: an arc of circle is used as the border div { border-top-left-radius: 40%; }
	The box is not a square: an arc of ellipse is used as the border div { border-top-left-radius: 40%; }
	The background color is clipped at the border div { border-top-left-radius:40%; border-style: black 3px double; background-color: rgb(250,20,70); background-clip: content-box; }

Specifications

Specification	Status	Comment
CSS Backgrounds and Borders Module Level 3The definition of 'border-top-left-radius' in that specification.	Candidate Recommendation	Initial definition

Browser compatibility

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
border-top-left-radius	Chrome Full support 4 Full support 4 Full support 1 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Edge Full support 12 Full support 12 Full support 12 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Firefox Full support 4 Notes' Full support 4 Notes' Notes' Prior to Firefox 50, border styles of rounded corners were always rendered as if border-style was solid. This has been fixed in Firefox 50. Full support 49 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit- Full support 44 Prefixed' Disabled' Prefixed' Implemented with the vendor prefix: -webkit- Disabled' From version 44: this feature is behind the layout.css.prefixes.webkit preference (needs to be set to true). To change preferences in Firefox, visit about:config. No support 1 — 12 Alternate Name' Alternate Name' Uses the non-standard name: -moz-border-radius-topleft	IE Full support 9	Opera Full support 10.5 Full support 10.5 Full support 15 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Safari Full support 5 Full support 5 Full support 3 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	WebView Android Full support ≤37 Full support ≤37 Full support ≤37 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Chrome Android Full support 18 Full support 18 Full support 18 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Firefox Android Full support 4 Notes' Full support 4 Notes' Notes' Prior to Firefox 50, border styles of rounded corners were always rendered as if border-style was solid. This has been fixed in Firefox 50. Full support 49 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit- Full support 44 Prefixed' Disabled' Prefixed' Implemented with the vendor prefix: -webkit- Disabled' From version 44: this feature is behind the layout.css.prefixes.webkit preference (needs to be set to true). To change preferences in Firefox, visit about:config. No support 4 — 14 Alternate Name' Alternate Name' Uses the non-standard name: -moz-border-radius-topleft	Opera Android Full support 11 Full support 11 Full support 14 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Safari iOS Full support 4.2 Full support 4.2 Full support 1 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-	Samsung Internet Android Full support 1.0 Full support 1.0 Full support 1.0 Prefixed' Prefixed' Implemented with the vendor prefix: -webkit-
Elliptical corners	Chrome Full support 1	Edge Full support 12	Firefox Full support 3.5	IE Full support 9	Opera Full support 10.5	Safari Full support 3	WebView Android Full support ≤37	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 14	Safari iOS Full support 1	Samsung Internet Android Full support 1.0
Percentages	Chrome Full support 4	Edge Full support 12	Firefox Full support 4 Full support 4 Full support 1 Notes' Notes' Before Firefox 4, the <percentage> was relative to the width of the box even when specifying the radius for a height. This implied that -moz-border-radius-topleft was always drawing an arc of circle, and never an ellipse, when followed by a single value.	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 14	Safari iOS Full support 4.2	Samsung Internet Android Full support 1.0

Legend

Full support  

Full support

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.

Requires a vendor prefix or different name for use.'

Requires a vendor prefix or different name for use.

See also

• border-radius shorthand property
• border-top-right-radius, border-bottom-right-radius, and border-bottom-left-radius

border-top-left-radius by Mozilla Contributors is licensed under CC-BY-SA 2.5.