robots.txt Validator
Validate robots.txt syntax — user-agents, allow/disallow, sitemaps, wildcards. Catch the Disallow: / that deindexed everything — local validation, free, no signup.
How to Use the robots.txt Validator
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Frequently Asked Questions
What breaks sites most?
A stray 'Disallow: /' (often staged-to-prod leftover) deindexes entire domains. The validator flags global disallows and contradictory rules immediately.
Wildcard and $ syntax?
Google supports * wildcards and $ end-anchors; not all crawlers do. Keep critical rules to plain prefixes for universal bots.
Sitemap declaration?
List sitemap URLs absolutely (https://…) — one line each. Validators confirm reachability, not just syntax.
Is my file uploaded?
No — validation runs locally in your browser. Nothing leaves your device.
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Last updated October 2026