# CRLite: Fast, private, and comprehensive certificate revocation checking in Firefox

DevFeed: [CRLite: Fast, private, and comprehensive certificate revocation checking in Firefox](<https://devfeed.tech/articles/crlite-fast-private-and-comprehensive-certificate-revocation-checking-in-firefox-4145.md>)

Original publisher: [Read original article](<https://hacks.mozilla.org/2025/08/crlite-fast-private-and-comprehensive-certificate-revocation-checking-in-firefox/>)

Author: John Schanck

Published: 2025-08-19T16:03:19Z

Content type: article

Language: en

Sources: [Mozilla Hacks - the Web developer blog](<https://devfeed.tech/sources/mozilla-hacks-the-web-developer-blog.md>)

Topics: [Certificate Transparency](<https://devfeed.tech/topics/certificate-transparency.md>), [Cryptography](<https://devfeed.tech/topics/cryptography.md>)

Tags: [browser](<https://devfeed.tech/tags/browser.md>), [certificate-transparency](<https://devfeed.tech/tags/certificate-transparency.md>), [encryption](<https://devfeed.tech/tags/encryption.md>), [feature](<https://devfeed.tech/tags/feature.md>), [firefox](<https://devfeed.tech/tags/firefox.md>), [http](<https://devfeed.tech/tags/http.md>), [linux](<https://devfeed.tech/tags/linux.md>), [macos](<https://devfeed.tech/tags/macos.md>), [performance](<https://devfeed.tech/tags/performance.md>), [privacy](<https://devfeed.tech/tags/privacy.md>), [security](<https://devfeed.tech/tags/security.md>), [tls](<https://devfeed.tech/tags/tls.md>), [windows](<https://devfeed.tech/tags/windows.md>)

## AI overview

Firefox's CRLite locally checks revoked TLS certificates using a compact, periodically updated encoding derived from Certificate Transparency logs. The article contrasts this approach with real-time OCSP checks, emphasizing privacy, reliability, and performance.

## Source excerpt

Firefox is now the first and the only browser to deploy fast and comprehensive certificate revocation checking that does not reveal your browsing activity to anyone (not even to Mozilla). Tens of millions of TLS server certificates are issued each day to secure communications between browsers and websites. These certificates are the cornerstones of ubiquitous [...] The post CRLite: Fast, private, and comprehensive certificate revocation checking in Firefox appeared first on Mozilla Hacks - the Web developer blog.