A private alternative to Spam Bully
Klar filters spam on your Mac, inside Apple Mail. No account, no cloud, nothing to hand over.
If you are weighing up Spam Bully, here is how Klar differs and where each one is the better pick.
| Aspect | Klar | Spam Bully |
|---|---|---|
| Runs on | Your Mac | Your Windows PC |
| Who can read your mail | No one new during filtering. Classification stays on your device. | A Bayesian filter plus allow/block lists, running inside Outlook, Windows Mail or Windows Live Mail |
| Works with | Apple Mail, with any account: IMAP, Gmail, iCloud, Exchange | Outlook, Outlook Express, Windows Mail and Windows Live Mail, on Windows only |
| Price | Free forever | Not published on their site |
Klar fits better when you read mail on a Mac: Spam Bully only integrates with Windows mail clients
The honest picks
- Spam Bully
- A Windows-only plugin for Outlook and Windows Mail. It combines Bayesian filtering with allow and block lists by address, word, country or language, plus a challenge system for unknown senders. Fine if you run Outlook on Windows. There is no Mac version.
- 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 and August 2026: spambully.com. Klar is not affiliated with any vendor named here. No vendor endorses Klar. Product names only identify the tools.
Reclaim your inbox
Spam filter for Apple Mail. Free on the App Store.
