Trezor Bridge

What Is Trezor Bridge?

Trezor Bridge is a small, lightweight background service that enables secure communication between your Trezor hardware wallet and web browsers or web-based applications. It acts as an intermediary (or “bridge”) so that browsers (which often restrict direct USB access) can still detect and interact with the Trezor device via a local interface.

Without Bridge, web‑based wallet tools (like the Trezor Suite web interface or integrations with third‑party platforms) might not be able to see or communicate with your hardware wallet—especially in browsers or environments that don’t support WebUSB or WebHID fully.

How Trezor Bridge Works

At a high level, this is how Bridge fits into the stack:

1. You plug your Trezor device into a USB port on your computer.
2. Trezor Bridge (running in the background) detects the device on your local machine.
3. Your browser-based wallet application sends JSON/HTTPS/WebSocket requests to Bridge (often through `localhost` or a loopback interface).
4. Bridge forwards those requests to the hardware wallet, which performs the requested cryptographic operations (e.g. fetching public keys, signing a transaction).
5. The signed data or response is passed back through Bridge to your browser application.

Importantly, the private keys never leave the Trezor device. Bridge is only a communication channel; it does not have access to your recovery seed or secret keys.

Note: In some modern browsers (e.g. recent Chrome or Chromium-based browsers), WebUSB or WebHID support is available, allowing direct connection without needing Bridge. But Bridge remains essential in many environments (Firefox, cross-platform compatibility, older browser versions). :contentReference[oaicite:0]{index=0}

// Example using TrezorConnect (JavaScript)
import TrezorConnect from '@trezor/connect';

TrezorConnect.getAddress({
  path: "m/44'/0'/0'/0/0"
}).then(response => {
  if (response.success) {
    console.log('Address:', response.payload.address);
  } else {
    console.error('Error:', response.payload.error);
  }
});

Installation & Setup

Installing Trezor Bridge is straightforward. Here’s a typical workflow:

• Visit the official Trezor website (e.g. via trezor.io/start).
• Download the correct installer for your operating system (Windows, macOS, Linux).
• Run the installer and follow prompts. Bridge will then run silently in the background as a service or helper process.
• Restart your browser and reconnect your Trezor device.

After installation, the web interface should automatically detect Bridge. If not, you may need to refresh, clear browser cache, or verify Bridge is running (check system tray / menu bar).

If Bridge is not detected (or you see a prompt to “install Bridge”), verify that you downloaded the correct installer, ensure no firewall or security software is blocking loopback ports, and make sure your browser allows local connections.

On the developer side, Trezor provides libraries (e.g. trezor-connect) to integrate with Bridge. :contentReference[oaicite:1]{index=1} Also, there is a PHP client library called trezor-bridge-client that communicates with the Bridge backend. :contentReference[oaicite:2]{index=2}

FAQ & Common Issues

Do I always need Trezor Bridge?

No. If you use the Trezor Suite desktop application (not the web interface), it often includes its own direct USB support, and Bridge is not required. Also, if your browser fully supports WebUSB or WebHID for your OS, Bridge may not be necessary. :contentReference[oaicite:3]{index=3}

What browsers / environments require Bridge?

Browsers like Firefox or older versions lacking WebUSB support typically need Bridge. :contentReference[oaicite:4]{index=4} Also, in Tor Browser or highly restricted environments, Bridge might not be detected. :contentReference[oaicite:5]{index=5}

Bridge is installed but my web app doesn’t detect it. What can I do?

Some troubleshooting steps:

• Ensure Bridge is actually running (check system tray/menu bar or process list).
• Restart your browser or computer.
• Clear browser cache or site data.
• Try a different USB cable or port.
• Make sure no firewall or security software is blocking local ports or loopback connections.
• Update Bridge to the latest version from the official site.

Is Trezor Bridge secure?

Yes, when obtained from the official source. Bridge only handles communication, never has access to your private keys or recovery seeds. Every sensitive operation (like signing) must be confirmed on the physical Trezor device itself. :contentReference[oaicite:6]{index=6} However, **never download Bridge from untrusted or phishing websites**—malicious versions may compromise security.