Verify DNS and port 80 are ready for Let's Encrypt issuance. Free lets encrypt check domain.
The Let's Encrypt Readiness Checker verifies that a domain is prepared for obtaining a certificate via Let's Encrypt (or any ACME-compatible CA). Let's Encrypt typically uses the HTTP-01 challenge: the CA asks your server to serve a specific token at a known path over HTTP on port 80. This tool checks that the domain resolves to an IP you control, that port 80 is reachable, and optionally that no firewall or redirect would block the challenge. It may also check for common issues such as the domain pointing to a CDN that does not forward to your server or port 80 being closed. Use it before running Certbot or another ACME client to reduce issuance failures. It does not issue a certificate; it only validates that the environment is ready for the challenge.
The CA gives you a token; you place it at http://yourdomain/.well-known/acme-challenge/... . The CA fetches it over HTTP on port 80.
Let's Encrypt uses port 80 for HTTP-01. If you only have HTTPS, you may need to allow temporary HTTP or use DNS-01.
Ensure the CDN forwards requests for /.well-known/acme-challenge/ to your origin, or use DNS-01 challenge instead.
Wildcards require DNS-01. This checker focuses on HTTP-01 readiness for non-wildcard certs.
No. It only checks readiness. Use Certbot or another ACME client to actually obtain the certificate.