SSL Certificate Checker / Utilities
SSL utilities
Small certificate tools for the jobs around a renewal. All but the preload check run in your browser, so a pasted key or certificate never leaves the page.
Certificate Decoder
Read a PEM certificate or chain: names, dates, key, extensions, fingerprints.
runs in your browser
CSR Decoder
Check a certificate signing request before you send it.
runs in your browser
Certificate and Key Matcher
Does this private key belong to this certificate or CSR?
runs in your browser
PEM and DER Converter
PEM to DER and back, with the openssl commands for the rest.
runs in your browser
CAA Record Generator
Allow only your certificate authorities to issue for your domain.
runs in your browser
HSTS Preload Checker
Is the domain on the preload list, and would it pass?
asks hstspreload.org
Certificate Lifetime Calculator
The CA/Browser Forum's shrinking lifetimes, for any issue date.
runs in your browser