Thunderbird
A free email, calendar and contacts app that works with any mail provider.
Instead of Gmail's web app and Outlook
Screenshot from www.thunderbird.net, taken 2026-10-23, shown to help you recognise the tool. It belongs to its maker. Ask us to remove it.
Thunderbird is part of the Mozilla family, says it is free forever and is funded by user donations. It combines mail, calendar and contacts, with a unified inbox, tags, filters and extensions, on Windows, Mac, Linux and Android. It works with the mail accounts you already have, so it lets you leave Gmail's interface without leaving your address.
Because it keeps mail on your own computer and speaks standard protocols, you can switch providers without losing your archive, which is why it does well on Lock-in and Longevity. It is a mail app and not a mail service, so it does not replace your provider, and its look is older than the web apps. We could not confirm its licence from its site.
- Mail, calendar and contacts in one app from the Mozilla family
- Works with the mail accounts you already have
- Keeps mail on your own computer and speaks standard protocols
What stands out
Do you make Thunderbird? Get the badge for your site
This badge reports a dated review. It is not a certification and it costs nothing. Link it to this page and leave the numbers alone: the image always shows the current score.
For dark backgrounds, use thunderbird-dark.svg in place of thunderbird-light.svg.
For comparison, we also reviewed Gmail (16/30) as a benchmark.
