Ultra‑light, Blazing‑fast & Privacy‑First Email Client

Cold start ≤1.5s · Sync 100 emails ≤3s · Idle memory ≤80MB · Local instant search

Built for power users with massive inboxes

Available for Windows, macOS, and Linux

ColiMail Application Screenshot

Engineered Performance Targets

Designed for speed, optimized for efficiency

≤1.5s
Cold Start
Launch to usable interface
≤3s
Sync 100 Emails
Initial incremental sync
≤80MB
Idle Memory
Baseline idle footprint
<50ms
Query Latency
Local indexed search
≤30MB
Package Size
Windows installer size

All metrics are target values under continuous optimization. Actual performance may vary based on hardware and email volume.

Built for Performance

Lightning fast, privacy-first email client.

Speed

Instant Local Search

Index millions of emails, query in <50ms.

Ultra-light Footprint

Idle memory ≤80MB with optimized threads.

Optimized Sync

Sync 100 recent emails in ≤3s.

Productivity

Multi-Account Support

Gmail, Outlook & custom IMAP/SMTP.

Rich Composer

Attachments, formatting, autosave drafts.

Folder Management

Efficient organization & filtering.

Privacy

Offline & Private

All data stored locally in SQLite.

No Telemetry

Zero tracking or analytics.

Secure Tokens (Planned)

Platform encryption for OAuth tokens.

Reliability

Background Sync

Stay up-to-date with minimal resource use.

Robust Index

SQLite-based high performance store.

Attachment Handling

Fast uploads & inline previews.

Lightning-Fast Search

Local indexing enables millisecond queries without remote server delays.

team@company.com2024-11-01

Q4 Performance Review

Your quarterly review is ready...

newsletter@tech.io2024-11-02

Weekly Tech Digest #42

Top stories this week in technology...

support@service.com2024-11-03

Ticket #1234 Resolved

Your support ticket has been resolved...

info@store.com2024-11-03

Order Confirmation #5678

Thank you for your purchase...

alerts@bank.com2024-11-02

Account Statement Available

Your monthly statement is now available...

💡 Interactive demo showing local indexed search response time

Instant Results

Type and search, <50ms response

Full-Text Index

Sender, subject, body coverage

Fully Offline

No network dependency, private

Privacy & Security

Your data belongs to you. Privacy protection is our top priority.

Local SQLite Storage

Email metadata and content stored locally. Fully offline capable, no cloud exposure risk.

Zero Telemetry

No usage data collection, no behavior tracking, no analytics reporting.

OS Keychain Protection

Passwords & OAuth2 tokens stored in OS keychain (Windows Credential Manager / macOS Keychain) with system-level encryption.

OAuth2 Secure Auth

Gmail & Outlook OAuth2 support. Tokens auto-chunked to bypass platform length limits.

Open Source Transparency

MIT licensed open source. All code auditable, community-driven, no hidden backdoors.

Direct IMAP/SMTP

Direct connection to email servers, no intermediary proxies, transparent communication.

✅ Implemented: Passwords and OAuth2 tokens migrated to OS keychain, no longer stored in app database.

📋 Current: Email content and attachments stored locally in plaintext. Future versions will implement AES-GCM encryption with user key.

How ColiMail Compares

See how ColiMail outperforms traditional email clients on key metrics.

Cold Start Time

ColiMail ≤1.5s
Thunderbird ~8s
Outlook ~5s
Apple Mail ~3s

Idle Memory

ColiMail ≤80MB
Thunderbird ~400MB
Outlook ~500MB
Apple Mail ~200MB

Package Size

ColiMail ≤30MB
Thunderbird ~150MB
Outlook ~2GB
Apple Mail Built-in

Local Search

ColiMail <50ms
Thunderbird ~500ms
Outlook ~200ms
Apple Mail ~100ms

Sync 100 Emails

ColiMail ≤3s
Thunderbird ~10s
Outlook ~8s
Apple Mail ~5s

Multi-Account

ColiMail
Thunderbird
Outlook
Apple Mail

OAuth2 Support

ColiMail
Thunderbird
Outlook
Apple Mail

No Telemetry

ColiMail
Thunderbird
Outlook
Apple Mail

Cross-Platform

ColiMail Win/Mac/Linux
Thunderbird Win/Mac/Linux
Outlook Win/Mac
Apple Mail Mac only

Benchmarks measured on Windows 11, i7-12700K, 16GB RAM. Results may vary by system configuration.

Performance Benchmarks

Real-world performance comparison across key metrics.

Performance Benchmark Comparison

ColiMail's advantage in key performance metrics

Cold StartBetter Performance
ColiMail1.5s
19%
Thunderbird8s
Outlook5s
Memory UsageBetter Performance
ColiMail80MB
16%
Thunderbird400MB
Outlook500MB
Package SizeBetter Performance
ColiMail30MB
2%
Thunderbird150MB
Outlook2000MB
Search SpeedBetter Performance
ColiMail50ms
10%
Thunderbird500ms
Outlook200ms
Sync 100 EmailsBetter Performance
ColiMail3s
30%
Thunderbird10s
Outlook8s
Benchmark environment: Windows 11, i7-12700K, 16GB RAM

Benchmarks are updated with each major release to reflect the latest optimizations.

Version History & Roadmap

Track our progress and see what's coming next.

Released Versions

v0.6.0 Released
  • Fixed Google OAuth desktop flow with deep link protocol
  • Resolved authentication deadlock in callback handling
  • Enhanced OAuth callback page with success indicators
v0.5.0 Released
  • Complete Supabase authentication system
  • Email/password registration with verification
  • Google OAuth login integration
  • Guest mode for full offline functionality
v0.4.0 Released
  • 13 email provider presets (Yahoo, iCloud, Zoho, etc.)
  • Connection testing before account creation
  • OAuth2 email input validation
  • Improved IMAP compatibility with GMX and 163.com
v0.3.0 Released
  • OS-native credential encryption (Windows Keyring, macOS Keychain)
  • Removed plaintext password storage from SQLite
  • OAuth2 token encryption with automatic chunking
  • Secure token storage with hash-based keys

Planned Features

v0.7.0 Planned
  • AES-GCM encryption for local email content
  • Calendar integration with event management
  • Multi-language UI support (English, Chinese, Japanese)
  • Advanced email filtering and rules engine
v0.8.0 Planned
  • Log viewer UI in settings with export functionality
  • Subscription/billing management interface
  • Enhanced notification settings dialog
  • Contact management system
v1.0.0 Planned
  • Production-ready stable release
  • Full platform encryption for all sensitive data
  • Advanced search with filters and saved searches
  • Email templates and signatures

Want to see detailed changes? Check out the full changelog.

View Changelog

Stay Updated

Get notified about new releases and performance benchmarks.

Get Started

v0.5.0-fix2

Download ColiMail for your platform. Auto-detects your operating system.

Released on: 2025-11-01 · View Changelog

Windows 10+
macOS 11+ (Apple Silicon)
Linux (AppImage)
Package Checksums & Details
No package information available

Alternative Downloads