# Annex

> Annex is a free, open-source app (MIT licence) that turns another computer into a second monitor for yours, or shows its screen on yours. It works between Mac, Windows and Linux in any combination, over your local network, a cable, direct Wi-Fi or the internet, and is encrypted end to end. No account, no tracking.

- Modes: Extend (the other computer becomes a second display), Mirror (see and use its screen), Control (one mouse and keyboard for both, with a shared clipboard).
- Platforms: macOS 14 or later (Apple silicon and Intel); Windows 10 (2004) or 11 (x64 and ARM); Linux (Ubuntu, Debian, Fedora, openSUSE, Raspberry Pi OS; x86_64 and arm64).
- Any pairing works in either direction: Mac to Windows, Windows to Linux, Mac to Mac, and so on.
- Delay: about 8 ms on a direct link, with hardware video encoding. Extend matches the other screen's refresh rate, up to 240 Hz. Mirror goes up to 2560×1600 at 60 fps. HEVC when both computers support it, otherwise H.264.
- Links: local network, Ethernet, Thunderbolt or USB4 cable (Mac to Mac), direct Wi-Fi (Windows hotspot), peer-to-peer Wi-Fi (Mac to Mac), or the internet with a 6-character code.
- Security: TLS 1.3 over QUIC; computers pair once with a 6-digit PIN (SPAKE2, the PIN is never sent) and remember each other's keys.
- Privacy: on a local network Annex never talks to a server. Over the internet, the code server only swaps the two computers' addresses; a relay is used only when a network blocks a direct link, and it stays encrypted.
- Also: sound both ways, copy and paste, drag-and-drop file transfer, headless sharing (Raspberry Pi, Mac mini over SSH), automatic signed updates.
- Price: free. No paid version, no sign-up.

## Docs

- [Annex docs](https://getannex.dev/docs): install, pair, try every feature, shortcuts, troubleshooting, uninstall
- [Full docs and FAQ as one Markdown file](https://getannex.dev/llms-full.txt)
- [Extend](https://getannex.dev/docs#extend): The other computer becomes a second monitor. Drag windows onto it.
- [Mirror](https://getannex.dev/docs#mirror): See and use another computer's screen in a window or full screen.
- [Control](https://getannex.dev/docs#control): Use one mouse and keyboard for both. In Extend, the pointer crosses between screens.
- [Over the internet](https://getannex.dev/docs#internet): Connect two computers on different networks with a 6-character code.
- [Your own server and relay](https://getannex.dev/docs#own-server): Use your own code server or relay instead of Annex's.
- [A sharper picture (HEVC)](https://getannex.dev/docs#hevc): When both computers support HEVC, the picture is sharper at the same speed. Otherwise it's H.264.
- [Cable](https://getannex.dev/docs#cable): The fastest link. Annex uses it by itself when one is plugged in.
- [Direct Wi-Fi](https://getannex.dev/docs#direct-wifi): The Windows PC runs its hotspot and the other computer joins it: no router in between.
- [Peer-to-peer Wi-Fi](https://getannex.dev/docs#p2p): Mac to Mac with no network at all, over the link AirDrop uses.
- [Sound](https://getannex.dev/docs#sound): Hear the computer you're viewing, and send your microphone back.
- [Copy and paste](https://getannex.dev/docs#clipboard): Copy on one computer, paste on the other, while you control it.
- [Send files](https://getannex.dev/docs#files): Drag files across; they arrive in the other computer's Downloads folder, checked.
- [Scaling and refresh rate](https://getannex.dev/docs#display): Set the extended display like a real monitor: sharp, larger text, or 144 Hz.
- [No one at this screen](https://getannex.dev/docs#headless): Share a Raspberry Pi or Mac mini you only reach over SSH.
- [Updates](https://getannex.dev/docs#updates): Annex installs new versions for you, checked against a signature.
- [Logs for a bug report](https://getannex.dev/docs#logs): Annex keeps a log on your computer. It never sends it anywhere.
- [Troubleshooting](https://getannex.dev/docs#troubleshooting)

## Download

- [macOS (universal .dmg)](https://github.com/NRanjan-17/Annex/releases/latest/download/Annex-macos-universal.dmg)
- [Windows x64](https://github.com/NRanjan-17/Annex/releases/latest/download/Annex-Setup-x64.exe) · [Windows ARM](https://github.com/NRanjan-17/Annex/releases/latest/download/Annex-Setup-arm64.exe)
- [Linux (.deb, .rpm, or the install script)](https://github.com/NRanjan-17/Annex/releases/latest)
- macOS and Linux in a terminal: `curl -fsSL https://raw.githubusercontent.com/NRanjan-17/Annex/main/scripts/install.sh | sh`
- Windows in PowerShell: `irm https://raw.githubusercontent.com/NRanjan-17/Annex/main/scripts/install.ps1 | iex`

## Optional

- [Source code on GitHub](https://github.com/NRanjan-17/Annex)
- [All releases](https://github.com/NRanjan-17/Annex/releases)
- [Report a bug](https://github.com/NRanjan-17/Annex/issues)