Every SSL/TLS certificate ever issued for this name, indexed from public CT logs.
| domain | status |
|---|---|
| join.fastmail.comcrt.sh Let's Encrypt | expired 10mo ago |
| join.fastmail.comcrt.sh Google Trust | expired 10mo ago |
| join.fastmail.comcrt.sh Let's Encrypt | expired 10mo ago |
| join.fastmail.comcrt.sh Microsoft | expired 1y ago |
| join.fastmail.comcrt.sh Google Trust | expired 1y ago |
| www.fastmail.comcrt.sh Microsoft | expired 1y ago |
| www.fastmail.comcrt.sh Unknown Issuer | expired 1y ago |
| www.fastmail.comcrt.sh Unknown Issuer | expired 1y ago |
| www.fastmail.comcrt.sh Unknown Issuer | expired 1y ago |
| fastmail.comcrt.sh Let's Encrypt | expired 4mo ago |
| www.fastmail.comcrt.sh Unknown Issuer | expired 2y ago |
| *.fastmail.comcrt.sh GlobalSign | expired 6mo ago |
| fastmail.comcrt.sh Microsoft | expires in 1mo |
| join.fastmail.comcrt.sh Let's Encrypt | expired 18d ago |
| *.carddav.fastmail.comcrt.sh Microsoft | expired 2mo ago |
| join.fastmail.comcrt.sh Microsoft | expired 2mo ago |
| join.fastmail.comcrt.sh Google Trust | expired 2mo ago |
| www.fastmail.comcrt.sh Google Trust | expires in 2d |
# Python
$ pip install ct-radar
$ ct-radar fastmail.com | httpx -silent# Go
$ go install github.com/imfht/ct-radar-cli/cli@latest
$ ct-radar fastmail.com | nucleiThis page lists every X.509 (SSL/TLS) certificate ever issued for fastmail.com and its subdomains, as recorded in public Certificate Transparency (CT) logs. CT logs are an immutable, append-only record of every certificate issued by participating Certificate Authorities (CAs), as required by the major browsers since 2018.
Subdomain enumeration via CT logs is one of the highest-signal techniques in reconnaissance — every time a TLS certificate is issued, all Subject Alternative Names (SANs) on that certificate become public. Internal and forgotten subdomains regularly show up here days after they're set up.
To monitor fastmail.com for newly-issued certificates in real-time (useful for detecting unauthorized issuance, phishing variants, or shadow IT) add it to your watchlist (Pro plan).