What is Trezor Bridge?
Trezor Bridge is a small helper app you install on your computer. Its job is simple but crucial: provide a reliable, secure channel for the browser or Trezor Suite to talk to your Trezor device over USB. Because web browsers have limited native USB access and varying levels of platform support, Bridge fills the gap in a secure, vendor-maintained way.
Why Bridge Matters
Hardware wallets protect your private keys by keeping them off your host computer. But to sign transactions, the host application still needs to send transaction data and request user confirmations. Bridge ensures this communication happens locally — not through a cloud service — reducing exposure to remote attacks. It also solves compatibility and permission issues across operating systems and browsers, ensuring a consistent user experience.
How Bridge Works — An Overview
Bridge runs as a background process on your machine and exposes a local API endpoint. When you open Trezor Suite or use the web app, that application connects to Bridge which then talks to the Trezor device over USB. All signing operations occur on-device: Bridge only transports the data and receives the signed result back to forward it to the app. At no time does Bridge store or transmit your private keys externally.
Security Considerations
- Local-only communication: Bridge uses localhost endpoints and never uploads signing material to third-party servers.
- Signed firmware checks: Bridge assists the Suite in verifying device firmware signatures so you only run authenticated firmware.
- Minimal attack surface: Bridge is intentionally lightweight. It only facilitates USB communication and has a narrow functional scope.
Installing Bridge — Quick Steps
Install Bridge from official sources only. Common steps:
- Download Bridge for your OS from the official download page (links below).
- Run the installer, grant required permissions, and allow the background process to start.
- Open Trezor Suite or the web app; the software should detect Bridge automatically and find your connected device.
Troubleshooting Common Issues
If your device isn't detected or Bridge fails to start, try these actions:
- Restart Bridge or your computer. Often a simple restart clears USB stack issues.
- Use the original USB cable and a direct port on your computer (avoid unpowered USB hubs).
- Check that Bridge is allowed through your firewall or antivirus; Bridge communicates only over localhost, but some software blocks local processes by default.
- Reinstall Bridge from the official download page if files appear corrupted.
Best Practices
To keep the Bridge + hardware wallet setup secure and predictable:
- Only download Bridge and Suite from the official manufacturer site or verified app stores.
- Keep Bridge and Trezor Suite up to date; updates may include security patches and compatibility fixes.
- Confirm transaction details on the Trezor device screen before approving any operation; the device display is the ultimate source of truth.
- If you're using a web browser version of Suite, prefer a browser with robust security and avoid public or untrusted machines.
Advanced Usage & Developer Notes
Developers building integrations can interact with Trezor devices using the Bridge protocol or the official integration libraries. Bridge exposes a documented local API for device discovery and communication. When developing, remember that the device must always approve sensitive operations and that the private key material never leaves the device.
Bridge vs Native Browser USB (WebHID/WebUSB)
Modern browsers provide APIs like WebUSB and WebHID which allow hardware interaction directly from web pages. However, browser support and permission behavior vary across platforms and can change over time. Bridge provides a stable, supported path that reduces fragmentation and helps maintain consistent security behavior across environments.
Privacy & Data Handling
Bridge does not collect or transmit personal data. It operates as a local proxy, forwarding messages between your machine's applications and the connected Trezor device. Transaction metadata may pass through the local connection during signing but is not sent to any cloud endpoint as part of Bridge's operation.
Where to Get Help
If you run into problems or want to learn more, use the official resources below. Support guides, FAQs, and developer documentation cover installation, advanced configuration, and troubleshooting details.
Final Thoughts
Trezor Bridge plays a small but vital role in the overall hardware wallet ecosystem: it ensures your device communicates reliably and securely with host applications while keeping private keys physically isolated on the hardware. By following installation best practices, staying up to date, and verifying transactions on-device, you preserve the strongest available protections for self-custody.