Certificate audit
rule.school SSL certificate check
SEO page with a cached certificate, TLS and chain-of-trust inspection result.
SSL certificate
Validity
Valid
Days remaining
87
Chain status
Trusted chain
Issuer
CN=YR1,O=Let's Encrypt,C=US
Subject
CN=rule.school
Valid from
9/4/2026 12:03:44 AM
Valid until
12/3/2026 12:03:43 AM
TLS version
TLS 1.2
Cipher
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
Subject alternative names
rule.schoolwww.rule.schoolCertificate chain
Certificate 1 /leaf
rule.school
Issuer: CN=YR1,O=Let's Encrypt,C=US
Until: 12/3/2026 12:03:43 AMCA: falseSelf-signed: false
Certificate 2 /intermediate
YR1
Issuer: CN=Root YR,O=ISRG,C=US
Until: 9/2/2028 11:59:59 PMCA: trueSelf-signed: false
Certificate 3 /last-presented
Root YR
Issuer: CN=ISRG Root X1,O=Internet Security Research Group,C=US
Until: 9/2/2032 11:59:59 PMCA: trueSelf-signed: false