Head to head
Klar vs Microsoft 365
What actually differs: where each filter runs, who gets to read your mail, and what it costs.
| Aspect | Klar | Microsoft 365 |
|---|---|---|
| Runs on | Your Mac | Microsoft's cloud |
| Who can read your mail | No one new. Your mail never leaves the device. | Microsoft processes your mail to filter it |
| Works with | Apple Mail, with any account: IMAP, Gmail, iCloud, Exchange | Microsoft 365 and Exchange Online mailboxes |
| Price | Free | Included |
Klar fits better when You want a second, local pass you control, for work and personal accounts alike
The honest picks
- Microsoft 365
- Exchange Online Protection is on for every Microsoft 365 mailbox and your admin manages it. On a work account, that decision is usually made for you. Klar still helps with what reaches Apple Mail.
- 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.
