Trezor Bridge — What it is and how it works

Purpose in plain words

Trezor Bridge is a small background application that helps your Trezor hardware wallet talk securely with a web browser on your computer. It acts as a translator and gatekeeper — translating browser requests into the USB protocol the device understands while ensuring the connection stays private and local to your machine. Without Bridge or an equivalent connection layer, many modern browsers block direct hardware access for security reasons, so Bridge is the safe bridge (pun intended) between your browser-based wallet apps and the physical device.

Installing and updating

The installer is available for Windows, macOS, and Linux. Download directly from the official Trezor website to avoid counterfeit or tampered copies. After running the installer, Bridge typically starts automatically and runs in the background; browsers then detect it and allow web wallet apps (like Trezor Suite or compatible third-party sites) to communicate with the device. Keep Bridge updated — updates often include security patches, compatibility fixes, and improvements for newer browser versions.

How the connection works

When you visit a compatible web app and choose to connect your Trezor, the site requests a local connection via Bridge. Bridge authenticates the request and opens a secure local channel to the device. Crucially, the only things transmitted are cryptographic commands and confirmations — your private keys never leave the physical device. Approvals for transactions happen on the Trezor screen, so even if your computer is compromised, the attacker cannot sign transactions without your device and your explicit confirmation.

Troubleshooting tips

• If your browser can’t see the Trezor, first check that Bridge is running. On Windows, look for the Bridge icon in the system tray; on macOS check the menu bar or Activity Monitor.
• Try a different USB cable or port — some cables are power-only and do not transfer data.
• Temporarily disable browser extensions that modify local connections (privacy blockers or proxy extensions) and test again.
• Reinstall Bridge if it fails to start or behaves erratically; a fresh install resolves many edge-case problems.
• Always use official downloads and verify checksums if they are provided.

Security considerations

Bridge itself is intended to be minimal and local. It does not upload keys or sign transactions — it simply forwards messages to the connected device. However, because it provides a local communication path, ensure your computer is kept up to date and free from malware. Avoid installing untrusted browser extensions and only approve actions on the Trezor screen after you confirm the details match what you expect.

Best practices

Use a dedicated USB cable you know is data-capable, run Bridge from the official source, and keep both Bridge and your device firmware up to date. When using public or shared machines, avoid connecting your hardware wallet; even though the device secures keys, connecting to unknown systems introduces avoidable exposure. Finally, back up your recovery seed in a secure, offline location — Bridge simplifies connectivity, but seed safety remains your most important responsibility.