Fast, free developer diagnostics

Every web check you need, in one place

DNS, blacklists, HTTP headers, dig & nameserver diffs, crawlability for search engines and AI, plus your own connection info. No sign-up required.

All tools

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DNS Lookup

All record types for any domain, plus a cross-nameserver consistency check.

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Blacklist Check

Check an IP or domain against 16+ DNS blacklists (RBLs) in one go.

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HTTP Headers

Status code, full redirect chain and every response header for a URL.

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Crawlability & AI

robots.txt, meta robots, sitemaps and per-bot access incl. AI crawlers.

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My Connection

Your public IP address, ISP, location and the browser you are using.

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