What is Trezor Bridge?
Trezor Bridge is a small, trusted background application that handles secure communication between your desktop browser and a Trezor hardware wallet connected via USB. Instead of relying on legacy browser plugins or exposed low-level USB APIs, Bridge provides a controlled, OS-level channel for payloads: device discovery, signing requests, firmware updates, and encrypted data exchange.
Why Bridge exists (short answer)
Modern browsers restrict direct USB access for security reasons. Bridge acts as the sanctioned middle layer — lightweight, vendor-signed installers for Windows, macOS, and Linux — letting Trezor Suite and web-based flows securely talk to your device without exposing sensitive USB details to random web pages.
How Bridge works (technical overview)
Device discovery
When you plug in your Trezor, Bridge detects the device and makes it available to authorized apps. Detection is limited to specific vendor/product IDs, preventing accidental exposure of unrelated devices.
Session authorization
Bridge forwards requests only when the user interacts and authorizes a session. Trezor's UX — confirm on the device — ensures private keys never leave the hardware.
Encryption & integrity
All exchanges between the application and device are payload-restricted and signed where necessary. Bridge does not hold your seed or private keys; it simply transmits encrypted commands to the Trezor unit.
Installing Trezor Bridge
Installation is intentionally simple: download the installer for your OS from the official page, run the package, and allow the small background service to start. Below are step-by-step tips for each major platform.
Windows (recommended steps)
- Download the Windows installer from the official Bridge page.
- Run the installer as administrator and follow prompts.
- After installation, plug in your Trezor — Windows should enumerate the device.
- Open
https://suite.trezor.ioor the Trezor web app to proceed.
macOS
On macOS, download the .dmg, drag Bridge to Applications, and allow the kernel extension if prompted (newer macOS versions require only user approval). You may need to confirm the system prompt under System Settings → Privacy & Security.
Linux
Bridge supports multiple distributions. Use the packaged installer or Flatpak where available. If you use a WebUSB-compatible browser, Bridge still simplifies device access for apps that require it.
Troubleshooting common issues
Browser doesn't detect Trezor
Check that Bridge is running (look for the Bridge icon or background service). Restart the browser, replug the device, and ensure you are using an official Trezor site (e.g., Trezor Suite) to initiate the session.
Bridge installation fails
On Windows, ensure you have admin privileges. On macOS, confirm security settings didn't block the installer. For Linux, check dependencies and that udev rules are installed for USB access.
Device stuck during firmware update
If an update stalls, do not disconnect power abruptly. Consult the official firmware guidance and use Trezor Suite's recovery/update tools. If the device is unresponsive, the Trezor team provides recovery steps on the official Support page linked above.
Security best practices
Trezor Bridge is designed with minimal attack surface. That said, follow these recommended practices:
- Only download Bridge from the official site (see the colorful links above).
- Keep Bridge and Trezor Suite up to date; updates include security hardening and bug fixes.
- Confirm every transaction on the Trezor device screen; never authorize blind prompts from a browser window.
- Use a trusted, malware-free OS environment — Bridge cannot protect against a compromised host.
- When finished, unplug your Trezor if you're on a shared machine.
How Bridge compares to WebUSB
WebUSB allows browser-based USB access, but it can be limited across browsers and poses additional security considerations. Bridge provides a consistent, OS-level interface that Trezor developers control; it reduces fragmentation and simplifies support across platforms.
Advanced tips
Running Bridge headless or in corporate environments
Administrators can deploy Bridge silently or bundle it using enterprise deployment tools. Check Trezor's support documentation for command-line installer options and corporate deployment notes.
Logging and diagnostics
Bridge can produce logs for troubleshooting. When contacting support, attach relevant logs (being careful not to share private keys or seed phrases — logs will never include them, but always verify before sending).
FAQ
- Do I need Trezor Bridge to use my hardware wallet?
- Bridge is required for some desktop/browser integrations (especially older flows). Trezor Suite bundles the necessary connectivity, and some modern browsers support direct connections — but Bridge remains the recommended, supported method for consistent behavior.
- Is Trezor Bridge safe?
- Yes — Bridge is a minimal service focused on secure device communications. It does not store recovery seeds or private keys. Always install Bridge from the official site to avoid counterfeit installers.
- Can I use my Trezor on multiple computers?
- Yes. You can install Bridge on each machine you trust. Your seed stays on the device; installing Bridge elsewhere does not expose your funds.
- What if Bridge stops working after an OS update?
- Reinstall the latest Bridge build from the official site. Also ensure your browser and OS USB permissions haven't changed after the update.
- How do I update Bridge?
- Download and run the latest installer from the official Bridge page. Trezor Suite may prompt you when updates are available.
Quick reference: commands & links
Helpful shortcuts:
- Official Bridge page: trezor.io/bridge
- Download Trezor Suite: suite.trezor.io
- Support & troubleshooting: trezor.io/support