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Home/Categories/Business & Productivity/Thunderbird
Thunderbird logo

Thunderbird

Open source alternative to Superhuman

Thunderbird is a free, open source desktop email client from MZLA, with unified accounts, powerful search and filters, built-in OpenPGP encryption, a calendar, and add-ons.

140 starsJavaScriptMPL-2.0Active this week
Visit websiteGitHub repo
Thunderbird screenshot
Contents
  1. 01What Thunderbird does
  2. 02Tech stack
  3. 03Similar open-source tools
TL;DR

Thunderbird is a free, open source desktop email client from MZLA, with unified accounts, powerful search and filters, built-in OpenPGP encryption, a calendar, and add-ons.MPL-2.0 · JavaScript · 140 stars · Active this week

what it does

What Thunderbird does#

Thunderbird is a free, open source desktop email client from MZLA, with unified accounts, powerful search and filters, built-in OpenPGP encryption, a calendar, and add-ons.

tech stack · detected from GitHub

What it's built on#

Languages
CC++JavaJavaScriptPythonRust
Tooling
esbuildRollup
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Repository

Stars
140
Forks
51
License
MPL-2.0
Last commit
1 day ago
Last verified
Sep 11, 2026
Repo
thunderbird/thunderbird-desktop ↗

Additional details

Language
JavaScript
Open issues
1
Contributors
1,806
First release
2025

Categories

Business & Productivity