W3C Feed Validation Service
VerifiableW3C's feed validator, which fetches a user-submitted RSS or Atom feed to check it against the feed specifications. It is a one-off conformance check rather than a subscription fetcher, and W3C publishes its user agent and the shared validator source addresses.
Operated by World Wide Web Consortium (W3C) · Official documentation
User agents
Patterns this directory matches, with real observed strings.
- regexFeedValidator/[\d.]+
- observedFeedValidator/1.3
How to verify
Documented static ranges: 52.22.66.203/32, 2600:1f18:7d7a:2700::/56
IP ranges (2)
Refreshed daily from the operator's feed. Also available as /data/ips/w3c-feed-validator.ips and /data/bots/w3c-feed-validator.json.
2600:1f18:7d7a:2700::/56 52.22.66.203/32
Good Bot Practices scorecard
- Identifies honestly
Stable UA token documented (1 pattern)
- Verifiable
Verifiable
- Respects robots.txt
Does not honor robots.txt
- Behaves
Crawl-rate behavior is operator-declared; not machine-verifiable from this dataset
- Reachable operator
Operator and documentation published
Measured against the Good Bot Practices.