--- title: Signal canonical: https://saasranked.com/software/signal/ category: Secure Messaging Apps points: 67 rank: 5 of 12 facts_checked: 2026-10-08 --- # Signal Free, open-source messenger from a nonprofit, with end-to-end encryption on every chat and apps for five systems. 67 points out of 100. #5 of 12 secure messaging apps. Vendor: Signal Foundation. Website: https://signal.org/ - The app is free for everyone; development is supported by grants and donations [1]. - Encryption is not an optional mode: Signal says privacy is simply how the app works [1]. - Apps exist for Windows, macOS, Linux, iOS and Android; desktop apps need Signal installed on a phone first [2]. - Signal still needs a phone number to sign up, though usernames let contacts reach you without seeing it [8]. - Android, iOS and Desktop code is public under AGPL-3.0 on GitHub [6]. Verdict: Signal suits people who want strong default privacy at no cost, with public code and post-quantum key exchange [1][3][6]. Secure Backups are end-to-end encrypted and optional [5]. The catch: you must register with a phone number, and no web app is listed [2][8]. Best for: People who want private chats by default and open-source apps, and accept sharing a phone number. ## Points | Criterion | Line | Value | Points | Note | |---|---|---|---|---| | Encryption | End-to-end encrypted by default | Yes | 12/12 | Signal says privacy is not an optional mode; all conversations use end-to-end encryption, and group calls are described the same way [1][9]. | | Encryption | Post-quantum key exchange | Yes | 4/4 | PQXDH, hybrid X25519 plus Kyber, is in use for chats started on current apps (2023). A post-quantum ratchet is rolling out [3][4]. | | Encryption | Encrypted backups | Yes | 4/4 | Secure Backups are opt-in and end-to-end encrypted; a 64-character recovery key made on your device unlocks them [5]. | | Source and audits | Open-source apps | Yes | 8/8 | Android, iOS and Desktop repositories are public under AGPL-3.0 [6]. | | Source and audits | Independent audit since 2022 | Not published | 0/10 | Neither post links an audit report from a named outside firm; the ratchet post names research and verification partners [3][4]. | | Source and audits | Public bug bounty | No | 0/4 | Help centre: Signal does not have a bounty program but investigates reported flaws [15][11]. | | Source and audits | Transparency report | Not published | 0/4 | The Government Requests page lists individual legal demands, latest 6 March 2026. It does not call itself a report or state a period [7]. | | Sign-up and identity | No phone number needed | No | 0/12 | Signal says you still need a phone number to sign up [8]. | | Sign-up and identity | Contacts by username | Yes | 4/4 | Share a username, link or QR code to connect without handing out your phone number [8]. | | Chats and calls | Disappearing messages | Yes | 5/5 | Timers apply per one-to-one chat or group, and the help centre allows custom times up to 4 weeks [16][12]. | | Chats and calls | Largest group chat | 1000 | 3/4 | Help centre: group chats have a size limit of 1000 [13]. | | Chats and calls | Encrypted voice and video calls | Yes | 5/5 | Group calls are end-to-end encrypted, 'like everything else on Signal'; the home page lists voice and video calls and says privacy is not optional [1][9]. | | Systems | Apps | Windows, macOS, Linux, iOS, Android | 10/12 | The download page lists all five; no web app and no beta labels [2]. | | Systems | Windows works without the phone | Yes | 4/4 | Help centre describes linked devices that keep connecting to Signal while the phone has not connected for a while [14]; Desktop links to a phone first [2][10]. | | Price | Cost for one person | $0 | 8/8 | The app is free for everyone; optional Secure Backups are an extra and are ignored [1][5]. | ## Plans | Plan | Price | Per month (USD) | |---|---|---| | Signal | Free [1] | $0 | | Secure Backups paid tier | $1.99/month [5] | $1.99 | Secure Backups are an optional extra and the price may change, as the launch post states [5]. ## Strengths - Free for everyone; development is supported by grants and donations [1]. - Uses PQXDH, a hybrid post-quantum key agreement, for chats started on current versions [3]. - Opt-in Secure Backups are end-to-end encrypted with a 64-character recovery key made on your device [5]. - Contacts can add you by username, link or QR code without seeing your phone number [8]. - Group chats hold up to 1,000 members [13]. ## Limits - A phone number is still required to sign up [8]. - No web app is listed; the desktop app needs Signal on a phone first [2]. - Signal's posts name research and verification partners but link no audit report [4]. - Secure Backups beyond the free tier cost $1.99 a month [5]. - Signal has no bug bounty program [15]. ## Vendor claims (not scored) - Signal says its post-quantum ratchet is being rolled out slowly and will be enforced for all sessions once all clients support it [4]. ## Sources 1. [Signal: Speak Freely](https://signal.org/), Signal, accessed 2026-10-08 2. [Download Signal](https://signal.org/download/), Signal, accessed 2026-10-08 3. [Quantum Resistance and the Signal Protocol](https://signal.org/blog/pqxdh/), Signal, accessed 2026-10-08 4. [Signal Protocol and Post-Quantum Ratchets](https://signal.org/blog/spqr/), Signal, accessed 2026-10-08 5. [Introducing Signal Secure Backups](https://signal.org/blog/introducing-secure-backups/), Signal, accessed 2026-10-08 6. [signalapp](https://github.com/signalapp), GitHub, accessed 2026-10-08 7. [Government Requests](https://signal.org/bigbrother/), Signal, accessed 2026-10-08 8. [Keep your phone number private with Signal usernames](https://signal.org/blog/phone-number-privacy-usernames/), Signal, accessed 2026-10-08 9. [Adding Encrypted Group Calls to Signal](https://signal.org/blog/group-calls/), Signal, accessed 2026-10-08 10. [signalapp/Signal-Desktop](https://github.com/signalapp/Signal-Desktop), GitHub, accessed 2026-10-08 11. [Security overview, signalapp/Signal-Android](https://github.com/signalapp/Signal-Android/security), GitHub, accessed 2026-10-08 12. [Disappearing messages for Signal](https://signal.org/blog/disappearing-messages/), Signal, accessed 2026-10-08 13. [Group chats](https://support.signal.org/hc/en-us/articles/360007319331-Group-chats), Signal, accessed 2026-10-08 14. [Open Signal on your phone to keep your account active](https://support.signal.org/hc/en-us/articles/9021007554074-Open-Signal-on-your-phone-to-keep-your-account-active), Signal, accessed 2026-10-08 15. [How can I report a security vulnerability?](https://support.signal.org/hc/en-us/articles/360007320791-How-can-I-report-a-security-vulnerability), Signal, accessed 2026-10-08 16. [Set and manage disappearing messages](https://support.signal.org/hc/en-us/articles/360007320771-Set-and-manage-disappearing-messages), Signal, accessed 2026-10-08