TOOL
HTML Validate
Validate HTML by checking tag balance: every opened tag must be closed. Tags inside comments are counted as real tags, so commented-out markup like <!-- <div> --> is reported as an unclosed tag.
Try an example:
Local only
Recent history
No history yet
How to use
- Type or paste your input into the input box.
- Adjust any parameters if needed.
- Copy or download the result.
Frequently asked questions
- Is my data uploaded anywhere?
- No. All processing happens locally in your browser with no server round-trip.
- Does this tool work offline?
- Yes. Once the page loads, the tool runs entirely client-side and needs no network connection.
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