Document: compatMode property
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The Document.compatMode
read-only property indicates
whether the document is rendered in Quirks mode or
Standards mode.
Value
A string that is one of the following:
"BackCompat"
if the document is in quirks mode."CSS1Compat"
if the document is in no-quirks (also known as "standards") mode or limited-quirks (also known as "almost standards") mode.
Note: All these modes are now standardized, so the older "standards" and "almost standards" names are nonsensical and no longer used in standards.
Examples
js
if (document.compatMode === "BackCompat") {
// in Quirks mode
}
Specifications
Specification |
---|
DOM # ref-for-dom-document-compatmode① |
Browser compatibility
Report problems with this compatibility data on GitHubdesktop | mobile | |||||||||||
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compatMode |
Legend
Tip: you can click/tap on a cell for more information.
- Full support
- Full support
- Partial support
- Partial support
- Has more compatibility info.
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.