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W3C Validator

Validate HTML and check markup errors

DevelopmentAuth: NoneHTTPS: YesCORS: unknownStatus: alive

Last verified: November 12, 2026

Reliability

100% uptime: the documentation responded in 5 of 5 checks over the last 30 days. Median response time: 223 ms.

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At a glance

// Fetch the docs page with cURL curl https://validator.w3.org/docs/api.html

History

  • November 12, 2026: last health check, responding

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