Tox is a peer-to-peer instant-messaging and video-calling protocol that offers end-to-end encryption. The stated goal of the project is to provide secure yet easily accessible communication.
The Tox core is a library establishing the protocol and API. User front-ends, or clients, are built on the top of the core. Anyone can create a client utilizing the core. Tox uses the cryptographic primitives present in the NaCl crypto library, via libsodium. Specifically, Tox employs Curve25519 for its key exchanges, xsalsa20 for symmetric encryption, and Poly1305 for MACs.
Tox is licensed under the GNU General Public Licence v3.0.
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Click the links in the table below to learn more about each client.
| Tox Clients | |
|---|---|
| qTox | Instant messaging, video conferencing with a simple and intuitive interface |
| Toxic | ncurses based client which formerly resided in the Tox core repository |
| µTox | Lightweight Tox client with minimal dependencies |
| Venom | Modern client written in Vala |
| Toxygen | Powerful cross-platform client written in Python |
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Tox offers the following features:
- Traffic encryption – One-to-one conversations, end-to-end encryption. All traffic over Tox is end-to-end encrypted using the NaCl library, which provides authenticated encryption and perfect forward secrecy. Tox employs Curve25519 for its key exchanges, xsalsa20 for symmetric encryption, and Poly1305 for MACs.
- Transparency of IP address to friends – Tox doesn’t cloak your IP address when communicating with friends.
- Social features – including group messaging, voice and video calling, voice and video conferencing, typing indicators, message read-receipts, file sharing, profile encryption, and desktop streaming, integrated links preview, messages likes, and music playing.
- Instant messaging – including customizable sets of emojis, stickers and animated GIFs.
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Historic comments have been retained.
Using an encrypted messaging app is no privacy panacea.
Enforcement agencies can crack the encryption. Just look at Sky ECC as a recent example.