How to use Stylesheet Compatibility Auditor
- Paste the stylesheet text without importing remote files.
- Choose one of the supported browser-family records.
- Review detected features, snapshot date and unknown scope before downloading.
Example: Stylesheet Compatibility Auditor
Scan literal CSS features against a small pinned browser-support subset, with recorded conditions and unassessed syntax.
You add
Stylesheet text: ".cards { display: grid; gap: 1rem; container-type: inline-size; }\n.card:has(img) { aspect-ratio: 16 / 9; }"
Browser record: "safari"
You get
5 selected CSS features found; snapshot 2026-10-03.
Options
- Browser record
- The result gives recorded support versions and conditions, not a test of your installed browser.
- Literal detection
- The scan ignores comments and quoted strings. Escapes, variable expressions and undetected syntax remain unassessed.
Supported inputs and limits
Up to 200,000 characters. Twelve selected CSS records from pinned MDN BCD v8.1.4, snapshot 3 October 2026; seven browser families. No full CSS grammar validation, remote imports or compatibility certificate.
Where your input is processed
This tool processes your input in this browser. Your text and files are not uploaded to UseFreeTools. Check this tool's limits for anything it may save on your device.
A feature table is not stylesheet certification
A supported property can still be used incorrectly or combined with an unsupported expression. Conditional flags, prefixes and partial implementation remain visible in the report. Test the actual page in the browser versions used by your audience rather than removing unknown syntax solely from this scan.
Questions about Stylesheet Compatibility Auditor
Is the data live?
It is the dated bundled snapshot shown with the result.
Does zero detected features mean compatible?
No. Undetected syntax remains unassessed.
Does it apply my stylesheet?
The text is inspected without applying styles to this page.