Developer ToolsCode ValidatorsFree Tool
robots.txt Validator
Check a robots.txt file for a User-agent directive and confirm every non-comment line has the expected colon syntax.
How to Use robots.txt Validator
- 1Paste your robots.txt content
- 2Click Process
- 3Review the User-agent/rule counts and any flagged syntax issues
Frequently Asked Questions
It confirms at least one 'User-agent:' line exists, flags any non-comment line missing a colon, and counts your User-agent blocks and Allow/Disallow rules.
No — it only checks basic line syntax, not the semantic effect of your rules (e.g. whether a Disallow pattern actually matches the URLs you intend). Test actual URL behavior with Google Search Console's robots.txt tester.
Not fully — it's a lightweight syntax check, not a spec-compliant parser. It won't catch every edge case the formal specification defines.
No — the check runs entirely in your browser.
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