PGP-first email · a K-Ops Oy product

Email only you and the people you write to can read.

Korax is an email client where encryption is the default, not a plugin. Signing, encryption and key management are part of your everyday inbox — across desktop and mobile.

Download for Linux View on Gitea

Linux available now macOS · Android · iOS coming soon

Beta · Pro free

Korax desktop — keypair identity view with private key available

End-to-end encrypted

Native PGP — not a plugin

No tracking pixels

Local-first — works offline

Keys in the OS secure enclave

Why Korax

TLS protects the wire. It doesn't protect the message.

We've had “secure” email for twenty years — yet messages still sit readable at rest, processable by providers, filterable, and in some places blocked outright for carrying PGP headers.

Korax was born from a simple frustration: most apps can't read an encrypted email out of the box. Reading PGP mail meant one specific Linux laptop — not a MacBook, not a phone, not while travelling.

“As soon as encryption enters the picture, the experience collapses back to the early 2000s. This project exists to close that gap.”

So Korax makes encryption a default capability — no separate toolchain, no extensions — that works naturally on every device you actually use.

Encryption by default

Compose an encrypted message as naturally as plain text. Signing and decryption are built into the everyday flow — nothing to install, nothing to configure.

No separate toolchain

Generate, import and manage keys inside the app. No GPG agent, no command line, no copy-pasting armored blocks between windows.

Everywhere you read mail

Encrypted mail that works on desktop and mobile alike — the way people expect to use email in 2026.

Usability, not sacrifice

Security shouldn't mean a worse experience. Korax balances verifiability, usability and resilience — for everyone, every day.

Features

Everything you need to keep mail between you and them.

PGP encryption & signing

Native, not a plugin. Compose encrypted mail as naturally as plain text — encryption and signatures are first-class, not bolted on.

Built in

TOFU trust model

“Trust On First Use,” with visual indicators: see at a glance whether a contact's key is known, trusted, or has changed.

Verified at a glance

No tracking pixels

Remote images are blocked by default. Autoload only for contacts whose public key you've saved — senders can't see when you open a message.

Local-first

All messages cached in SQLite on your device. Instant load, fully offline, nothing sent to any cloud.

Multi-language

English, German, Spanish, Finnish, Russian and Swedish — Korax speaks your language out of the box.

Linux: always free

Always fully unlocked on Linux. No paywall, no nag screens — the honor system, for the platform that made encrypted mail possible.

Always Pro

One inbox, every device

Light or dark. Phone or desktop. Always encrypted.

The same first-class PGP experience whether you're at your desk or on the move — keys, trust indicators and all.

Unified inbox

Your keys, in-app

Read & reply

Free vs Pro

A one-time purchase. Free for everything that matters.

Feature	Free	Pro
Send & receive email	✓	✓
IMAP accounts	Max 3	Unlimited
Basic PGP encryption / decryption	✓	✓
Generate PGP keypair	Max 1	Unlimited
PGP key import / export	View only	✓
Keyserver auto-lookup (WKD)	—	✓
Smart rules & filtering	—	✓
Unified inbox & custom swipe actions	—	✓
Burn-after-reading (Korax-to-Korax)	—	✓
Provider Hostility Detection & Korax Tunnel	—	✓
On LinuxAlways Pro	✓	✓

Pro is a one-time purchase — not a subscription. Linux is always fully unlocked.

Under the hood

Rust does the hard part. The UI never blocks.

                                Flutter UI
                                    (Dart)
                                    │
                                flutter_rust_bridge (FFI)
                                    │
                                Proprietary engine
                                    (Rust)
                                    │
                                mailcore
                                    (Rust · open source)
                                    ├──
                                    IMAP client
                                    ├──
                                    SMTP client
                                    ├──
                                    SQLite storage
                                    ├──
                                    MIME parser
                                    └──
                                    DNS SRV discovery
                            

Built for resilience.

All network and crypto operations run in Rust and reach Dart through a zero-copy FFI bridge — so the interface stays smooth while the heavy lifting happens underneath.

Flutter / Dart

Core engine

Rust

Cryptography

sequoia-openpgp

Storage

SQLite

State

Riverpod

Bridge

flutter_rust_bridge

mailcore is open source. The Rust engine at the heart of Korax is published for transparency and community audit under the PolyForm Noncommercial License 1.0.0.

Security model

Your keys never leave your device.

Keys in the secure enclave

Private keys are never written to disk in plaintext. They live in the OS secure store — iOS Keychain, macOS Keychain, Android Keystore.

Trust you can see

TOFU indicators show whether a key is known, trusted or changed — so a swapped key never slips by unnoticed.

Nobody watching you read

Remote content is blocked by default. No tracking pixels, no read receipts, no leaking when or where you opened a message.

Download

Get Korax for Linux.

A self-contained AppImage — no installation required. And on Linux, it's always fully unlocked.

Korax for Linux AppImage · x86_64

chmod +x Korax-x86_64.AppImage

./Korax-x86_64.AppImage

# Korax launches — no install, fully unlocked.

Download from Releases

macOS, Android & iOS — coming soon.