Klar: Spam Filter for Mail
AI spam filter, 100% on-device
Only for Mac
Free
Mac
Klar is an AI spam filter for Apple Mail that runs entirely on your Mac. No cloud, no automatic telemetry, no account required.
It catches the phishing, scam, and junk emails that Mail's built-in filter misses, using a multilingual transformer model fine-tuned on millions of real emails.
HOW IT WORKS
Klar installs as a Mail extension. Once enabled in Mail > Settings > Extensions, it classifies every incoming email automatically and moves spam to Junk.
You decide when that starts. For your first 30 days Klar flags spam in red and leaves it in your inbox, so you can see what it catches before trusting it; after that it moves spam to Junk on its own. It is a setting, so you can switch either way whenever you like.
The ML model runs locally on your Mac. No email is uploaded for classification. A report leaves only when you send its editable draft yourself.
FEATURES
- Real-time spam classification as emails arrive
- Multilingual: the model handles emails in any language automatically
- Optional Contacts whitelist: turn it on to keep verified mail from known senders in your inbox
- You decide what happens: move spam to Junk or flag it in red, and flag clean mail in green if you want to see the filter working
- A dashboard that shows how much mail Klar has been through and what it caught
- Zero network access: the extension has no network entitlement
PRIVACY
Klar is private by design. The extension is fully sandboxed with no network access. Your email content is processed on-device and Klar sends nothing automatically. No automatic telemetry, no account. If you choose Email report, Klar opens a draft in your mail app for you to review, edit and send yourself. The draft includes a removable summary of the previous month's local usage totals.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Klar now shows you its work before it moves anything.
- For your first 30 days, spam is flagged in red instead of being moved, so you can check what Klar catches before you trust it. After that it moves to Junk on its own, and you can pick either behaviour whenever you like.
- The dashboard counts the mail Klar has been through, lists what it caught, and keeps the rest of the history behind Show more.
- Got one wrong? Report several catches at once from the dashboard, with the original message attached so we can fix it.
- Klar explains why it needs your Contacts before macOS asks, and asks only once.
- The Aggressiveness setting now changes what the filter does. It was showing three choices and applying the most careful one whatever you picked.
- Clearer German and French throughout the app.
The developer, Nicolas HA, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Nicolas HA
- Size
- 410.3 MB
- Category
- Utilities
- Compatibility
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later.
- Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later.
- Mac
- Languages
English and 2 more
- English, French, German
- Age Rating
4+
- 4+
- Copyright
- © 2026 Nicolas HA