Free tool
RSS & Atom feed validator
Check an RSS 2.0 or Atom 1.0 feed against its specification: required channel and entry elements, date formats, self links and duplicate identifiers.
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Reference for these formats
RSS 2.0
The most widely deployed syndication format: namespace-free at its core, extension-heavy in practice, and unopinionated about almost everything.
Atom 1.0
The IETF-standardised syndication format: namespaced from the root, strictly typed, and unambiguous about dates in a way RSS 2.0 never was.
Hit a parse error? Every common XML error explained.
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Get started
Keep the documents you check, and watch them for changes.
A free workspace stores versions, extracts their structure for search, and re-checks monitored URLs on a schedule. Paste or upload up to 4 MB, or fetch a URL up to 5 MB.