DNS
THE CERTIFICATE BEHIND THE CONNECTION

TLS certificate checker.

Inspect SSL/TLS certificates for any public domain or subdomain.

Checks HTTPS on port 443, including subject alternative names, validity dates and the presented chain.

SSL certificate

TLSv1.3

mail.btcl.com.bd · 123.49.12.137:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. SSL operation failed with code 1. OpenSSL Error messages: error:0A000086:SSL routines::certificate verify failed
The certificate has expired.

Certificate verification failed

Subject
L=Dhaka OU=Domain emailAddress=aahmed.tanim@btcl.com.bd ST=Dhaka C=BD CN=mail.btcl.com.bd O=Bangladesh Telecommunications Company Limited
Issuer
L=Dhaka OU=Domain emailAddress=aahmed.tanim@btcl.com.bd ST=Dhaka C=BD CN=mail.btcl.com.bd O=Bangladesh Telecommunications Company Limited
Valid from
2022-01-06T10:05:34+00:00
Expires
2023-01-06T10:05:34+00:00
Days remaining
-1375
Serial (hex)
2B67C28F
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:mail.btcl.com.bd

SHA-256 fingerprint

72:8A:D5:83:E3:43:73:E9:36:67:B3:36:3C:5C:52:54:86:0F:9B:B2:3F:F7:93:F4:D3:88:F1:5F:D6:60:B8:CA
Certificate extensions & PEM
subjectKeyIdentifier
52:A6:56:E3:06:89:8F:19:14:2F:62:CF:6F:1A:5D:E4:18:51:D5:DA
basicConstraints
CA:FALSE
authorityKeyIdentifier
keyid:52:A6:56:E3:06:89:8F:19:14:2F:62:CF:6F:1A:5D:E4:18:51:D5:DA DirName:/L=Dhaka/OU=Domain/emailAddress=aahmed.tanim@btcl.com.bd/ST=Dhaka/C=BD/CN=mail.btcl.com.bd/O=Bangladesh Telecommunications Company Limited serial:2B:67:C2:8F
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
subjectAltName
DNS:mail.btcl.com.bd
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-10-11T19:17:42+00:00

One endpoint on port 443. Server-presented chain; no revocation, OCSP, CT or full TLS security scan.

View certificate JSON

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