Mozilla Thunderbird

Mozilla Thunderbird
Developers
Initial releaseJuly 28, 2003 (2003-07-28)
Stable release
Monthly release: 148.0.1 / 10 March 2026 
ESR: 140.8.1esr / 10 March 2026 
Preview release149.0beta  (25 February 2026) [±]
Written inC, C++, JavaScript, CSS, Rust, XUL, XBL
EnginesGecko, SpiderMonkey
Operating systemWindows 10 or later; macOS 10.15 or later; FreeBSD; Linux; Android
Size50 MB
Available in65 languages
List of languages
Albanian, Arabic, Armenian, Asturian, Basque, Belarusian, Breton, Bulgarian, Catalan, Chinese (Simplified), Chinese (Traditional), Croatian, Czech, Danish, Dutch, English (British), English (US), Estonian, Finnish, French, Frisian, Gaelic (Scotland), Galician, German, Greek, Hebrew, Hungarian, Icelandic, Indonesian, Irish, Italian, Japanese, Kabyle, Korean, Lithuanian, Lower Sorbian, Norwegian (Bokmål), Norwegian (Nynorsk), Polish, Portuguese (Brazilian), Portuguese (Portugal), Romanian, Romansh, Russian, Serbian, Sinhala, Slovak, Slovenian, Spanish (Argentina), Spanish (Spain), Swedish, Turkish, Ukrainian, Upper Sorbian, Vietnamese, Welsh.
TypePersonal information manager, Email client, Instant messaging client, News client, Feed reader
LicenseMPL-2.0
Websitewww.thunderbird.net
Repositoryhttps://hg-edge.mozilla.org/

Mozilla Thunderbird is a free and open-source personal information manager primarily used as an e-mail client with a calendar and contactbook, as well as an RSS feed reader, chat client (IRC/XMPP/Matrix), and news client. Operated by MZLA Technologies Corporation, a subsidiary of the Mozilla Foundation, Thunderbird is an independent, community-driven project that is managed and overseen by the Thunderbird Council, which is elected by the Thunderbird community. As a cross-platform application, Thunderbird is available for Windows, macOS, FreeBSD, Android, and Linux. The project strategy was originally modeled after that of Mozilla's Firefox, and Thunderbird is an interface built on top of that Web browser.