Alternative
A private alternative to SpamAssassin
Klar filters spam on your Mac, inside Apple Mail. No account, no cloud, nothing to hand over.
If you are weighing up SpamAssassin, here is how Klar differs and where each one is the better pick.
| Aspect | Klar | SpamAssassin |
|---|---|---|
| Runs on | Your Mac | Your mail server |
| Who can read your mail | No one new. Your mail never leaves the device. | Runs on your own server. Mail stays on your infrastructure. |
| Works with | Apple Mail, with any account: IMAP, Gmail, iCloud, Exchange | Server-side, in front of any mailbox (Postfix, Sendmail and other MTAs) |
| Price | Free | Free and open source |
Klar fits better when You read mail in Apple Mail and don't run your own mail server
The honest picks
- SpamAssassin
- The classic open-source filter: rules plus Bayesian scoring, two decades of deployment. Powerful once tuned, but it lives on a mail server you run and maintain, not on your Mac.For a lightweight self-hosted layer, see Klar for servers.
- Klar
- Pick Klar if you read mail in Apple Mail and want a modern multilingual model that runs entirely on your Mac. No account, no cloud, nothing to hand over.
Product and price details from the vendors' public pages, July 2026: c-command.com, sanebox.com, support.google.com, learn.microsoft.com, libraesva.com, spamassassin.apache.org, rspamd.com, mailinblack.com. Klar is not affiliated with or endorsed by any vendor named here; names are used only to identify the products.
The on-device option
Free, private, in Apple Mail.
