Astroid

At a glance

• Editor score
  3.0 / 10
• Pricing
  Open source
• Best for
  Power users preferring keyboard-driven email workflows
• Paid from
  Free
• App coverage
  Desktop
• Facts checked
  20 Sep 2026

• Where it wins

  • Free and open source on Windows, macOS, and Linux
  • Thread, tag, and Notmuch-backed search organization
  • PGP/MIME support with Python and Lua plugin extensibility

• Where it doesn't

  • Depends on separate programs for fetching, syncing, and sending email
  • Only Notmuch is listed as an integration
  • No scheduling, calendar, offline, or unified-inbox features

Our verdict on Astroid

Astroid is a lightweight desktop Mail User Agent for searching, displaying, organizing, and composing email. It is designed for technically oriented users who manage a local mail workflow, particularly those who prefer keyboard operation and Notmuch-backed indexing and search. Messages are presented in threads and tags, while inline HTML and attachment display keep common email content within the graphical interface. Astroid is free and open source across Windows, macOS, and Linux desktop platforms.

Its strongest fit is focused email organization rather than broad communication-suite coverage. Thread- and tag-based views, keyboard navigation, configurable themes, separate-window graphical buffers, and embedded or external editor support give power users control over how they read and compose messages. PGP/MIME cryptographic email support adds a privacy-oriented capability, while syntax highlighting for patches and code is relevant to technical workflows. Python and Lua plugins provide an extension path for users comfortable configuring their environment.

The trade-off is that Astroid sits inside a larger local mail setup. It relies on separate programs for fetching, synchronizing, and sending email, so it suits users who already manage those parts of their workflow. Notmuch is the listed integration, and the product does not provide scheduling, calendar, offline, or unified-inbox features. Choose Astroid for a free, open-source desktop client centered on search, threads, tags, cryptography, and keyboard control. Choose another email client if you want built-in mail transport, broader integrations, calendar features, or a unified inbox.

Your product? Our editors can test Astroid in depth and publish a review, labelled as paid · from $149/mo →

Astroid pricing

Astroid fact sheet

Astroid integrations

Astroid lists 1 integrations on its own site.

• Notmuch

Alternatives to Astroid

• Mozilla ThunderbirdA capable free client for multi-account email, offline access, and desktop productivity tools.9.4
• Zoho MailA flexible hosted email service with free access, migration tools, and Zoho collaboration options.9.2
• Apple MailA capable Apple-focused email client with unified inboxes, scheduling, privacy controls, and AI assistance.9.1

See all Astroid alternatives →

Featured on iTechGuides

Astroid is listed in our Email Clients directory. Add the badge to your site — it links back to this page.

<a href="https://www.itechguides.com/products/astroid/"><img src="https://www.itechguides.com/best/badge/astroid.svg" alt="Featured on iTechGuides" width="230" height="46"></a>

Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

Advertiser disclosure: iTechGuides is reader-supported. Vendors can pay for top positions in our rankings and for a place on other products' pages, and we may earn a commission when you click some links. Bought places stand at the number bought; this page and our disclosure say so. Paying vendors may get a fuller, more detailed review from our editors, and that review can change their score. How we rank.

Last updated 7 Oct 2026 · How we research and update