Head to head
Klar vs SpamSieve
What actually differs: where each filter runs, who gets to read your mail, and what it costs.
| Aspect | Klar | SpamSieve |
|---|---|---|
| Runs on | Your Mac | Your Mac |
| Who can read your mail | No one new. Your mail never leaves the device. | No one new. Processing stays on your Mac. |
| Works with | Apple Mail, with any account: IMAP, Gmail, iCloud, Exchange | Apple Mail, Outlook and other Mac clients |
| Price | Free | $39.99 one-time |
Klar fits better when Spam comes in several languages, or you don't want to train a filter
The honest picks
- SpamSieve
- A proven on-device filter with two decades of history. Pick it if you like Bayesian filtering you train yourself and want a mature indie tool. Klar takes a different bet on the model: a multilingual transformer instead of word statistics.
- 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.
