Klar

AI spam filter for Apple Mail. Runs locally on your Mac. Private by design.

EmailLaunched Aug 2026

The story

Klar is a free AI-powered spam filter for Apple Mail that runs entirely on your Mac. It uses a modern multilingual model to detect spam, phishing, and marketing emails across 100+ languages, moving unwanted messages to Junk automatically. With no account required and no cloud processing, Klar keeps your email private by architecture, not just by promise.

Overview

Klar is an AI-powered email filtering solution designed specifically for Apple Mail users who want spam protection without sacrificing privacy. The tool uses XLM-RoBERTa, a modern multilingual AI model, to classify incoming emails into four categories: regular mail, marketing, spam, and gibberish. Unlike cloud-based filters that read your mail on remote servers, Klar performs all processing locally on your Mac with zero network access, ensuring your emails never leave your device. The product supports over 100 languages with automatic detection and offers three sensitivity levels (Cautious, Standard, Aggressive) so users can control filtering aggressiveness. Klar is free forever with no account creation required, and works with any mail provider that Apple Mail supports, including iCloud, Gmail, Fastmail, Outlook, and custom IMAP accounts. An optional paid companion called Klar Plus, coming soon, will add a dedicated Marketing folder and allow the model to learn from user corrections.

Key features

On-Device Processing

All spam detection runs locally on your Mac with no network access, keeping your emails completely private.

Multilingual Support

Automatically detects and filters spam in over 100 languages without any configuration needed.

Three Sensitivity Levels

Choose between Cautious, Standard, and Aggressive filtering profiles to match your preferences.

Non-Destructive Filtering

Spam is moved to Junk, never deleted, so you can recover messages if needed.

Universal Mail Support

Works with iCloud, Gmail, Fastmail, Outlook, and any custom IMAP account that Apple Mail can access.

Background Processing

Filters emails as they arrive without slowing down Mail or requiring manual action.

Use cases

1
Privacy-Conscious Email Users
People who want spam protection without their emails being read or analyzed on remote servers.
2
Multilingual Users
Users receiving emails in multiple languages who need reliable spam detection across different language variants.
3
Mac Users
Apple Mail users on macOS 14 or later who want a native, integrated spam filtering solution.
4
High-Volume Email Recipients
Professionals receiving many emails daily who want automatic filtering to reduce inbox interruptions.

FAQ

Is Klar really free?

Yes. Klar's spam filtering is free and stays free forever. Klar Plus, an optional paid companion adding a Marketing folder and learning from corrections, is coming soon.

Does Klar send my emails to a server?

No. Classification runs entirely on your Mac. The app and extension have no network access. If you choose to send an email report, Klar opens a draft in your mail app for you to review and send yourself.

Which mail accounts does Klar work with?

Klar works with any mail account that Apple Mail supports: iCloud, Gmail, Fastmail, Outlook, and custom IMAP accounts.

What happens if Klar misclassifies a message?

You can drag the message back to the correct folder. With Klar Plus, corrections retrain the filter and trigger a nightly re-check of older mail.

Does Klar slow down Apple Mail?

No. Klar checks mail in the background, and classification takes only a few hundredths of a second per message.