Talk privately. Leave nothing behind.

C:\ghost>How it works

Four steps, all typed in the app. There is nothing to sign up for.

1. 1

   Create a room

   Type /create and choose how long the chat may last. You get a one-time room code.

2. 2

   Share the code

   Send it to the other person over a channel you trust. It works for 5 minutes, and only while you are waiting for them.

3. 3

   They join

   They type /join and paste the code. Both screens show Secure channel established and a short fingerprint you can compare.

4. 4

   Talk, then leave

   When either of you types /leave or closes the window, the chat ends and both screens are wiped. Nothing is kept.

C:\ghost>What you get

Each feature does one plain job.

No accounts

No phone number, email or username. Each session gets a random alias such as anon-31ac.

Nothing saved

Messages exist only in memory while the chat is open. The app keeps its working files in a temporary folder that is deleted when you close it.

Encrypted on your device

Only the two of you can read the messages. The server passes along scrambled data that it cannot open.

Exactly two people

A room holds two participants. If a third person tries to use the code, they are turned away.

A time limit you choose

When you create a room you set how long the chat may last, from 1 to 240 minutes. A warning appears 60 seconds before it closes and wipes everything.

Screen protection

The window is hidden from most screenshot and screen-recording tools on Windows. It cannot stop a camera pointed at your screen.

Locked copy and paste

The conversation cannot be selected or copied. Only the room code can be copied, and only a room code can be pasted, right after /join.

A typing indicator that shows nothing

The other person sees animated dots while you type, never what you type. Turn it off with /live off.

Optional Tor

With /tor the connection goes through the Tor proxy on your computer, so the server does not see your real IP address. Tor must already be running.

C:\ghost>Why you don't have to trust the server

The server never has the keys. It only passes scrambled data between two computers, and it forgets the room when the chat ends.

Everything that travels between the two computers is scrambled.

The details, for people who want them

Room code

A 12-character room name plus a secret of 128 bits. The secret never leaves your devices. The server only sees a hash of it.

Key exchange

A fresh X25519 key pair for every conversation, authenticated with the room secret so the server cannot swap keys.

Key derivation

HKDF with SHA-256 turns the shared result into the session key.

Messages

AES-256-GCM with a new random nonce for every message. Sequence numbers block replayed messages.

Padding

Messages are padded to 256-byte blocks, so their length gives little away.

Forward secrecy

Keys exist only for that conversation and are wiped when it ends, so an old recording cannot be opened later.

These are standard building blocks put together into a custom protocol. That protocol has not been reviewed by an independent security expert.

C:\ghost>What RelayChat does not protect

No chat app can do everything. These are the limits, stated plainly.

• It is a beta, and it is not audited. It was built and tested by one person. If your safety depends on it, use an established app that has been reviewed by independent experts.
• A camera beats any screen protection. Someone can photograph their screen, or simply retype what you wrote.
• Malware on your computer defeats it. A keylogger or screen-capture tool running on your PC sees what you see.
• Without Tor, the server sees your IP address. Encryption hides what you say, not the fact that you are talking. Use /tor if that matters.
• Whoever has the room code can join first. Send it over a channel you trust. If your contact sees "room is full", assume the code leaked and start a new room. When it matters, compare the fingerprint by another route.
• Windows may write memory to disk. Like any program, it can swap parts of memory to the page file. The app cannot prevent that.
• Windows only, for now. There is no phone version yet.

C:\ghost>Download and verify

One file, no installer. Check that the file you got is the file we published before you run it.

C:\ghost>Questions

Short answers.

C:\ghost>Support RelayChat

RelayChat is free and has no ads, because there is nothing to sell. If it is useful to you, a donation helps pay for the server and the domain, and for time to keep improving it.