Certificate Transparency
in Chrome

Recognized Logs

The following table includes information about the Certificate Transparency Logs that are recognized by Chromium. It includes information about who operates the log, the name the log has been given, and the URL that can be used for logging certificates or inspecting the certificates that have been logged.

Note: The authoritative list is maintained in the Chromium code base. This is merely informational.

Log Name Log URL Log State MMD Temporal Interval Start Temporal Interval End Log Operator Contact Info
Google ‘Argon2023’ log https://ct.googleapis.com/logs/argon2023/ Usable 86400 2023-01-01T00:00:00Z 2024-01-01T00:00:00Z Google google-ct-logs@googlegroups.com
Google ‘Argon2024’ log https://ct.googleapis.com/logs/us1/argon2024/ Usable 86400 2024-01-01T00:00:00Z 2025-01-01T00:00:00Z Google google-ct-logs@googlegroups.com
Google ‘Xenon2023’ log https://ct.googleapis.com/logs/xenon2023/ Usable 86400 2023-01-01T00:00:00Z 2024-01-01T00:00:00Z Google google-ct-logs@googlegroups.com
Google ‘Xenon2024’ log https://ct.googleapis.com/logs/eu1/xenon2024/ Usable 86400 2024-01-01T00:00:00Z 2025-01-01T00:00:00Z Google google-ct-logs@googlegroups.com
Cloudflare ‘Nimbus2023’ Log https://ct.cloudflare.com/logs/nimbus2023/ Usable 86400 2023-01-01T00:00:00Z 2024-01-01T00:00:00Z Cloudflare ct-logs@cloudflare.com
Cloudflare ‘Nimbus2024’ Log https://ct.cloudflare.com/logs/nimbus2024/ Usable 86400 2024-01-01T00:00:00Z 2025-01-01T00:00:00Z Cloudflare ct-logs@cloudflare.com
DigiCert Yeti2024 Log https://yeti2024.ct.digicert.com/log/ Usable 86400 2024-01-01T00:00:00Z 2025-01-01T00:00:00Z DigiCert ctops@digicert.com
DigiCert Yeti2025 Log https://yeti2025.ct.digicert.com/log/ Usable 86400 2025-01-01T00:00:00Z 2026-01-01T00:00:00Z DigiCert ctops@digicert.com
DigiCert Nessie2023 Log https://nessie2023.ct.digicert.com/log/ Usable 86400 2023-01-01T00:00:00Z 2024-01-01T00:00:00Z DigiCert ctops@digicert.com
DigiCert Nessie2024 Log https://nessie2024.ct.digicert.com/log/ Usable 86400 2024-01-01T00:00:00Z 2025-01-01T00:00:00Z DigiCert ctops@digicert.com
DigiCert Nessie2025 Log https://nessie2025.ct.digicert.com/log/ Usable 86400 2025-01-01T00:00:00Z 2026-01-01T00:00:00Z DigiCert ctops@digicert.com
Sectigo ‘Sabre’ CT log https://sabre.ct.comodo.com/ Usable 86400     Sectigo ctops@sectigo.com
Sectigo ‘Mammoth’ CT log https://mammoth.ct.comodo.com/ Retired 86400   2023-01-15 00:00:00Z Sectigo ctops@sectigo.com
Let’s Encrypt ‘Oak2023’ log https://oak.ct.letsencrypt.org/2023/ Usable 86400 2023-01-01T00:00:00Z 2024-01-07T00:00:00Z Let’s Encrypt sre@letsencrypt.org
Let’s Encrypt ‘Oak2024H1’ log https://oak.ct.letsencrypt.org/2024h1/ Usable 86400 2023-12-20T00:00:00Z 2024-07-20T00:00:00Z Let’s Encrypt sre@letsencrypt.org
Let’s Encrypt ‘Oak2024H2’ log https://oak.ct.letsencrypt.org/2024h2/ Usable 86400 2024-06-20T00:00:00Z 2025-01-20T00:00:00Z Let’s Encrypt sre@letsencrypt.org
Trust Asia Log2023 https://ct.trustasia.com/log2023/ Usable 86400 2023-01-01T00:00:00Z 2024-01-01T00:00:00Z TrustAsia trustasia-ct-logs@trustasia.com
Trust Asia Log2024-2 https://ct2024.trustasia.com/log2024/ Usable 86400 2024-01-01T00:00:00Z 2025-01-01T00:00:00Z TrustAsia trustasia-ct-logs@trustasia.com