Show HN: Detect paid Cloudflare plans on any website via ECH
1 rapawel 5 9/14/2025, 2:59:05 PM experiments.pawelpokrywka.com ↗
A tool that checks if any website uses a paid Cloudflare subscription by examining their public /cdn-cgi/trace endpoint. Cloudflare only allows disabling Encrypted Client Hello (ECH) in paid plans, so sni=plaintext indicates a paid subscription. Works on any Cloudflare-proxied site.
From what I've observed:
- Free plans: ECH is forcefully enabled (sni=encrypted)
- Paid plans: ECH is disabled by default (sni=plaintext), but can be manually enabled
The tool can only definitively distinguish between free plans and paid plans that use the default ECH settings.