Cloudflare Fundamentals - Retry-After HTTP header for retryable 1xxx errors

Cloudflare-generated 1xxx error responses now include a standard Retry-After HTTP header when the error is retryable. Agents and HTTP clients can read the recommended wait time from response headers alone — no body parsing required.

Changes

Seven retryable error codes now emit Retry-After:

Error code Retry-After (seconds) Error name 1004 120 DNS resolution error 1005 120 Banned zone 1015 30 Rate limited 1033 120 Argo Tunnel error 1038 60 HTTP headers limit exceeded 1200 60 Cache connection limit 1205 5 Too many redirects

The header value matches the existing retry_after body field in JSON and Markdown responses.

If a WAF rate limiting rule has already set a dynamic Retry-After value on the response, that value takes precedence.

Availability

Available for all zones on all plans.

Verify

Check for the header on any retryable error:

curl -s --compressed -D - -o /dev/null -H "Accept: application/json" -A "TestAgent/1.0" -H "Accept-Encoding: gzip, deflate" "<YOUR_DOMAIN>/cdn-cgi/error/1015" | grep -i retry-after

References:

• RFC 9110 section 10.2.3 - Retry-After ↗︎
• Cloudflare 1xxx error documentation