Notes 
Decentralized messenger that assigns no identifier to users, not even a random number. Contacts are established via one-time invite links or QR codes, with all data stored on-device only.
Reviewed by Gabriel Bachmann
SimpleX Chat
simplex.chat 4.7 (24)
Messaging Open Source E2E encrypted No account Decentralized Windows macOS Linux Android iOS Free United Kingdom
Rate SimpleX Chat: No account needed
Threat level
Targeted
A targeted-tier tool. Built for a real, capable adversary. Overkill for everyone below. Threat levels
Our take
No other mainstream messenger can honestly say it collects zero metadata about who talks to whom, because every other app still ties you to a phone number, email, or account ID. SimpleX routes messages through relays without linking sender and recipient on the server side, and the protocol has been audited by Trail of Bits. The real trade-off is setup friction: sharing an invite link is awkward compared to searching a username, so getting less tech-savvy contacts onboard takes effort. For high-stakes private communication, that friction is worth it.
GitHub at a glance
simplex-chat/simplex-chat AGPL-3.0 chatdouble-ratchete2eeencryptionhaskellmessagingprivacyprotocolsecurity
Stars
19,642
+35 this week
Forks
1,319
131 watching
Last commit
today
healthy
Latest release
v7.0.3
1mo ago, 100+ total
Star history
Issues
48% closed
1,024
open
928
closed
+21 / -7
opened / closed, last 4 weeks
Opened vs closed, last 12 weeks
Commits, last 26 weeks
315 commits, active 22 of 26 weeks
50 contributors since Dec 2019
Languages
- Haskell 33.6%
- Kotlin 27.5%
- Swift 23.2%
- Other 15.7%
Updated daily from the GitHub API. Star tracking since Jun 22, 2026.
Website at a glance
simplex.chat
C score 50
Basic website security headers
Graded by Mozilla HTTP Observatory, tested 2d ago
Inspect this site yourself
Measures the security configuration of the tool's own website, not the privacy of the product itself. A strong tool can still score low here.
SimpleX Chat alternatives
Signal Similar look and feel of WhatsApp and other commonly used messaging apps, makes switching easy. Signal requires your phone number as an personal identifier.
Delta Chat Delta Chat doesn't have their own servers but uses the most massive and diverse open messaging system ever: the existing e-mail server network. Chat with anyone if you know…
Brave Talk The person creating the call requires to use Brave Browser, but the participants can join from any browser.
Jitsi Meet Desktop version downloads can be found here .
Stoat Open source, self-hostable Discord alternative, formerly Revolt. Built for communities that want off Discord, but it is not end-to-end encrypted.
iMessage Apple's built-in messenger. End-to-end encrypted between Apple devices.
SimpleX Chat license, in plain English
AGPL-3.0 Strong copyleft · network
Free to use, even commercially. Changes must be published under the same license, and running a modified version as a network service counts as distributing it.
Permits
- Commercial use
- Modification
- Distribution
- Patent use
- Private use
Requires
- Disclose source
- Network use is distribution
- Same license
- State changes
- License and copyright notice
Does not provide
- Liability cover
- Warranty
Why it matters: The network clause is the point. Anyone who runs a modified version as a hosted service has to publish those changes, so the code handling your data stays inspectable. This is why privacy-first projects reach for AGPL.
Plain-language summary of the project's license, not legal advice. Read the full text for the exact terms.