01 — Versus
Signal is the gold standard of mainstream private messaging: fully open source, run by a nonprofit, and reviewed by cryptographers for over a decade. This page does not pretend otherwise. It is a precise account of where NoidChat and Signal differ, which rows each one wins, and how to choose. Differences, not marketing.
02 — Credit Where Due
Every messenger that claims to care about privacy gets measured against Signal, and that is fair. The Signal Protocol has been analysed by academic cryptographers for years. The clients and the server are open source. The organisation behind it is a nonprofit funded by donations, with no ads and nothing to sell. If you stop reading here and install Signal, you have made a good decision.
NoidChat exists because we wanted different answers to three specific questions. Should a messenger ever see a phone number? Should post-quantum parameters be something you can see and choose, on messages and on calls? And should a panic response destroy data rather than merely hide it? Our answers cost us some of the things Signal does better. The matrix below shows both sides of that trade.
03 — Feature Matrix
Eleven rows, no weasel words. Where Signal is ahead, the row says so.
| Category | Signal | NoidChat |
|---|---|---|
| Registration identity | Phone number required at signup. Optional usernames hide your number from other users, but the number still exists in the system. | None. Pick a username, set a password, start. No phone number, no email, no identity.
Edge: NoidChat |
| Server metadata | Sealed sender hides who is messaging whom, and court records from subpoenas have repeatedly shown near-zero retained data.
Edge: Signal |
No phone or email is ever collected, but the server routes ciphertext and can see who talks to whom. No comparable published transparency evidence yet. |
| Post-quantum encryption | Hybrid PQXDH key agreement, on by default for everyone: X25519 combined with ML-KEM, so an attacker must break both. A post-quantum ratchet has been announced to extend that protection. | Pure ML-KEM-768 (NIST Category 3) is the default for direct messages, files and voice notes. ML-KEM-1024 (Category 5) is one tap away per conversation.
Both default-on: hybrid vs pure |
| Encrypted calls | End-to-end encrypted voice and video, mature across all platforms. | ML-KEM-768 or ML-KEM-1024 handshake per session, then per-frame AES-256-GCM via WebRTC Insertable Streams. Dual-stack V1/V2 pipelines that never cross-wire. |
| Forward secrecy | Per-message forward secrecy via the Double Ratchet. Shipped, proven, analysed.
Edge: Signal |
Calls derive a fresh secret per session today. Per-message forward secrecy for chats is on the roadmap, not shipped. |
| Open source | Fully open source clients and server, stewarded by a nonprofit foundation.
Edge: Signal |
Selected encryption-layer components are public. The full application is not open source. Signal wins this row. |
| Platforms | Native iOS, Android and desktop apps, all mature.
Edge: Signal |
Web app and Android APK. Runs on iOS via Safari; a native iOS app is in development. Signal wins this row today. |
| Track record & review | Over a decade in production. Years of academic review and formal analysis of the protocol.
Edge: Signal |
Newer, with no comparable body of independent review yet. We state that plainly rather than hide it. |
| Panic features | Screen lock and disappearing messages. No duress wipe. | Hyper Protect: a deactivation PIN that, if entered, permanently destroys all your data. The account ceases to exist.
Edge: NoidChat |
| Contact verification | Safety numbers for out-of-band verification, available today.
Edge: Signal |
Rotating HMAC-signed QR codes (new code every 60 seconds) for adding friends. Out-of-band conversation verification is on the roadmap. |
| Funding model | Nonprofit, donation-funded. No ads, no data sales. | Independent private Australian company. No ads, no tracking. You are trusting a company's incentives rather than a nonprofit's charter — weigh that honestly. |
Note: NoidChat group chats currently use Roulette Cascade, an experimental multi-cipher mode, while ML-KEM coverage for groups is on the roadmap. Full implementation detail lives in the NoidChat security deep-dive.
04 — What Actually Differs
Signal's usernames solve a social problem: other users no longer see your phone number. They do not remove the number from registration. For most threat models that is fine — Signal stores remarkably little. But if the requirement itself is the problem, because you cannot safely use a number you own or you do not want a registration identity linking accounts together, NoidChat's answer is to never ask. There is nothing to hide because nothing was collected. We cover this in detail in messaging without a phone number.
Both apps take the harvest-now-decrypt-later threat seriously, and both run post-quantum key agreement by default for everyone — that already puts them ahead of most messengers. Signal hybridises: PQXDH combines X25519 with ML-KEM so an attacker must break both, which is the more conservative construction, and Signal has announced a post-quantum ratchet to carry that protection beyond the initial key agreement. NoidChat runs pure ML-KEM with parameters you can see and choose: 768 by default, 1024 opt-in for conversations that warrant Category 5. Calls get the same treatment — a post-quantum handshake, then every audio and video frame encrypted with AES-256-GCM in the browser. The theory is in our post-quantum encryption explainer.
Signal's answer to device seizure is a screen lock and disappearing messages. NoidChat adds a harder option: Hyper Protect. You set a deactivation PIN; if it is ever entered, all of your data is permanently destroyed and the account ceases to exist. It is deliberately destructive, built for the situation where a device can be seized and you can be compelled to unlock it. Most people will never need it. The people who need it, need exactly it.
05 — The Honest Recommendation
Running both is a legitimate answer. Both are free, and they solve overlapping but not identical problems.
06 — FAQ
There is no single answer, and anyone who gives you one is selling something. Signal is the safer default recommendation for most people: more platforms, fully open source, years of review. NoidChat is the better fit when no-identity registration, selectable post-quantum parameters, or a destructive duress PIN is what your situation requires.
Yes. Registration is a username and a password. No phone number, no email, no identity documents. Signal requires a phone number at signup; its usernames hide the number from other users but do not remove it. Details on the no-phone-number page.
No. Selected components of NoidChat's encryption layer are public, but the full application is not open source. Signal's clients and server are fully open source. On this criterion Signal is ahead, and we would rather say so than dodge the question.
Yes — PQXDH, a hybrid of X25519 and ML-KEM, on by default for everyone, with a post-quantum ratchet announced. The difference is construction: NoidChat runs pure ML-KEM, lets you pick 768 or 1024 per conversation, and extends the post-quantum handshake to calls with per-frame AES-256-GCM. Background reading: what post-quantum encryption actually is.
Yes. Both cost nothing. Plenty of people keep Signal for existing contacts and use NoidChat where a registration identity is unacceptable. They are not mutually exclusive.
07 — Try It