SimpleX Chat vs Threema
Two of the top three secure messaging apps, compared rule by rule on published facts.
In short
- SimpleX Chat has 86 points and Threema 79, 7 apart on our secure messaging apps rules.
- SimpleX Chat earns more on encryption, chats and calls, systems and price; Threema earns more on source and audits.
- Cost for one person: SimpleX Chat $0, Threema $6/yr.
- Only SimpleX Chat meets: post-quantum key exchange, disappearing messages and Windows works without the phone.
- Only Threema meets: public bug bounty and largest group chat.
86/100 #1 of 12
Best for: People who want a messenger that holds no account identifier or phone number.
Threema79/100 #2 of 12
Best for: People who want a messenger with no phone number and no subscription.
Points by group
| Group | SimpleX Chat | Threema |
|---|---|---|
| Encryption of 20 | 16 | 12 |
| Source and audits of 26 | 22 | 26 |
| Sign-up and identity of 16 | 16 | 16 |
| Chats and calls of 14 | 10 | 7 |
| Systems of 16 | 14 | 12 |
| Price of 8 | 8 | 6 |
| Total | 86 | 79 |
Rule by rule
What each vendor publishes, and the points it earns. Sources are on each product page.
| Rule (points) | SimpleX Chat | Threema |
|---|---|---|
| End-to-end encrypted by default (12) | Yes 12 | Yes 12 |
| Post-quantum key exchange (4) | Yes 4 | Not published 0 |
| Encrypted backups (4) | Not published 0 | Not published 0 |
| Open-source apps (8) | Yes 8 | Yes 8 |
| Independent audit since 2022 (10) | Yes 10 | Yes 10 |
| Public bug bounty (4) | Not published 0 | Yes 4 |
| Transparency report (4) | Yes 4 | Yes 4 |
| No phone number needed (12) | Yes 12 | Yes 12 |
| Contacts by username (4) | Yes 4 | Yes 4 |
| Disappearing messages (5) | Yes 5 | Not published 0 |
| Largest group chat (4) | Not published 0 | 256 2 |
| Encrypted voice and video calls (5) | Yes 5 | Yes 5 |
| Apps (12) | Windows, macOS, Linux, iOS, Android 10 | Windows, macOS, Linux, iOS, Android, Web 12 |
| Windows works without the phone (4) | Yes 4 | No 0 |
| Cost for one person (8) | $0 8 | $6/yr 6 |
SimpleX Chat
SimpleX Chat suits people who want to chat without handing over a phone number or any account ID, with open code and outside reviews behind it. Its transparency report covers 2025. The catch: no web app, calls are one-to-one only, and disappearing messages need set-up by the people involved.
Threema
Threema suits people who want a one-time purchase and an account that is not tied to a phone number. Its code is public, it publishes audit reports, and it lists government requests each year. The catch: the usual desktop app and web client need your phone online, and only a beta works without it. Group chats are capped at 256 members.
Both products are scored by the same rules: how we score secure messaging apps.