Short summary: Trezor Bridge is a small, secure helper application that enables your Trezor hardware wallet to communicate with web browsers and desktop software. It streamlines device connectivity while keeping your private keys offline.
Trezor Bridge is a local background application developed by SatoshiLabs that acts as a secure conduit between a Trezor device and web-based or desktop wallet interfaces. Instead of exposing low-level USB calls to the browser or third-party apps, Bridge provides a controlled, authenticated communication channel so you can manage accounts, sign transactions, and perform firmware updates safely.
Unlike browser extensions that require elevated permissions or outdated plugins, Bridge runs as a native process on your machine and handles transport, device discovery, and message routing. It is available for Windows, macOS, and Linux and is regularly updated to support new devices and security improvements.
When you plug in your Trezor device, the operating system detects the USB attachment. Bridge, running in the background, takes ownership of the connection and exposes a local HTTP or WebSocket API on your machine. Trusted wallet software connects to this local API and issues JSON-based commands (e.g., getPublicKey, signTx) which the Trezor firmware processes. The private keys never leave the secure element of the device — Bridge only transports signed responses and metadata.
Bridge also enforces origin checks: web pages using Trezor Connect must be allowed to communicate with Bridge, and the protocol prompts the user on the device for approval when sensitive actions occur (like signing a transaction).
1. Download the official Bridge package from the Trezor website or from the official GitHub release page. Always verify you are on the official domain (trezor.io) before downloading.
2. Run the installer appropriate for your operating system and follow on-screen prompts. On some platforms you may need to approve the app in System Preferences (macOS) or accept driver prompts (Windows).
3. Once installed, Bridge runs automatically. Open the Trezor Suite or a supported web wallet and follow the Connect prompts. Your browser will request permission to access Bridge; allow it only when you trust the site.
Tip: If you prefer not to run Bridge, the Trezor Suite desktop app bundles the necessary transport, or advanced users can use native USB support in compatible clients — but Bridge provides the simplest, most compatible path for most users.
trezor.io or the project's official channels. Avoid third-party mirrors.Bridge not detected: Check that the device is unlocked and the USB cable is data-capable. Try a different USB port or cable, and ensure your OS drivers are up to date.
Browser can't connect: Make sure Bridge is running — on some systems it shows as a tray or menu bar icon. Restarting Bridge or your browser often resolves ephemeral connection problems.
Firmware update failed: Do not disconnect the device during an update. If an update interrupts, follow official recovery steps documented on the Trezor support pages.
Multiple wallet clients conflict: If more than one app tries to access Bridge simultaneously, close the extras. Use the official Trezor Suite when possible to minimize compatibility issues.
Q: Is Bridge open source? A: Components of Trezor software are open source. Check the Trezor GitHub repositories for code, releases, and build instructions.
Q: Can Bridge read my recovery seed? A: No. Bridge never has access to your recovery seed or private keys — the device is designed so sensitive material remains on the hardware only.
Q: Do I need Bridge for mobile? A: Mobile workflows differ. Some mobile apps use native USB or Bluetooth adapters; Bridge is primarily for desktop and browser integrations.