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Home/Categories/Business & Productivity/Thunderbird
Thunderbird logo

Thunderbird

Open source alternative to Superhuman

  • 210 stars
  • MPL-2.0
  • Active this week
  • Last commit 1 day ago

Last verified Oct 20, 2026

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.

Visit websiteGitHub210 stars
Thunderbird screenshot
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.

Read the full breakdownHide the full breakdownWhat it does
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
Looking for more

Other ways to replace Superhuman#

Macro Mail

#2 in the Superhuman guide

Fast keyboard triage with chat, tasks, and agents attached

4,782 GitHub stars

Mailspring

#3 in the Superhuman guide

Fast desktop drop-in with a unified inbox

17,934 GitHub stars

NeoMutt

#5 in the Superhuman guide

Keyboard-first terminal triage

3,854 GitHub stars

Cypht

#6 in the Superhuman guide

Self-hosted unified webmail

1,768 GitHub stars
All 8 Superhuman alternatives7 open source Superhuman alternatives, ranked
by category

Open source tools in these categories#

191

Business & Productivity

OpenClaw, Excalidraw, RustDesk

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rakazo

Alternative toGrok Bot

AI teammates you own: your keys, your model, your machine.

  • 4,904 GitHub stars
  • Apache-2.0Licence Apache-2.0
  • #AI Agents

Omnara

Alternative toCClaude Managed Agents

Open-source agent deployment API. Self-host or use Omnara Cloud.

  • 2,957 GitHub stars
  • Apache-2.0Licence Apache-2.0
  • #AI Agents

Inbox Zero

Alternative toSuperhuman

AI email assistant that drafts replies and clears your inbox

  • 12,712 GitHub stars
  • AGPL-3.0Licence AGPL-3.0
  • #Email
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