ObsoleteThis feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.
Non-standard This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
The HTMLImageElement
interface's obsolete lowsrc
property can be used to specify the URL of a reduced-quality or otherwise faster-loading version of the image specified by the src
property.
This property reflects the HTML lowsrc
attribute.
Syntax
htmlImageElement.lowsrc = imageUrl; imageUrl = htmlImageElement.lowsrc;
Value
A DOMString
specifying the URL of a version of the image specified by src
which has been modified in some fashion so that it loads significantly more quickly than the primary image.
There are a number of ways to achieve this; primary among them:
- Higher compression levels (for example, a primary image saved as a JPEG using 85% quality might have a
lowsrc
version saved at 15%. - Reduced color depth; a primary image in 32-bit color might have an alternate image in 8-bit color.
Important: The lowsrc
property is obsolete and should not be used. Instead, you should use an image format which loads progressively (such as progressive JPEG). Or simply make sure your images are all well-optimized and balanced for appearance versus size.
Usage notes
lowsrc
is a strange case. It was never technically part of the HTML specification (it was a Mozilla extension to HTML); however, HTML 5 does list it among the obsolete attributes.
Browser compatibility
The compatibility table on 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
Full support 1 |
Edge
Full support ≤18 |
Firefox
Full support Yes |
IE
? |
Opera
Full support Yes |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
? |
Opera Android
? |
Safari iOS
? |
Samsung Internet Android
Full support Yes |
Legend
- Full support
- Full support
- Compatibility unknown
- Compatibility unknown
- Deprecated. Not for use in new websites.'
- Deprecated. Not for use in new websites.
HTMLImageElement.lowsrc by Mozilla Contributors is licensed under CC-BY-SA 2.5.