CSS Validator
Check CSS for rules that fail to parse, live as you type.
Checks each rule using the browser's own CSS parser (inserted into a real stylesheet, then removed) — it can say a rule failed to parse and name its selector, but not give the exact error text a dedicated CSS linter would. At-rules like @media aren't checked individually. Runs entirely in your browser; nothing you type is sent anywhere.
What is CSS Validator?
Paste CSS and this tool checks whether each rule parses using your browser's own CSS engine, flagging any that don't. It's a quick sanity check for a stray typo or malformed rule, not a full spec-compliance linter.
FAQ
No — browsers silently drop CSS they can't parse rather than throwing a detailed error, so this can say a rule failed and name its selector, but not give the precise reason.
Only top-level plain rules are checked individually; at-rules are not broken down further.