~/tools / ssl-checker

SSL Checker

Check SSL certificate expiry, chain validity, TLS version and cipher. Catches expired certs, weak crypto and chain issues.

>
[ OK ] Valid for 72 more days.
── output ─────
Issued to
slack.com
Issued by
R13
Valid from
2026-04-04
Valid until
2026-07-03 (72 days)
TLS version
TLSv1.3
Cipher
TLS_AES_256_GCM_SHA384
Key
RSA · 2048 bit
Signature
sha256WithRSAEncryption
Forward secrecy
yes
Self-signed
no
Must-staple
no
SHA-256 fingerprint
67:BE:C3:76:96:A8:04:37:9F:9A:CA:DB:BD:75:F7:73:92:FE:15:7A:13:6B:5D:37:B7:BD:D3:E6:69:6F:3F:94
Serial
05BD89B1D225CBC9EE966D81EC660D3EAC6A
subject_alt_names · 2
*.slack.com slack.com
certificate_chain · 2 certs
[ leaf ]slack.com
72 days left
issuer: R13
2026-04-04 → 2026-07-03
[ inter ]R13
325 days left
issuer: ISRG Root X1
2024-03-13 → 2027-03-12
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