Quick overview
Trezor devices are designed so sensitive operations (key storage, signing) happen on the hardware itself. However, operating systems and browsers place restrictions on direct USB access. Trezor Bridge fills that gap: it runs on your computer, exposes a controlled local API for apps and websites, and forwards requests securely to your device. Think of Bridge as a translator and gatekeeper — it improves compatibility without exposing your seed or private keys.
What Bridge does (and doesn’t)
- Enables connectivity: Makes Trezor devices discoverable to Trezor Suite and supported web apps across Windows, macOS, and Linux.
- Manages permissions: Ensures only authorized applications and origins can access the device.
- Keeps keys private: Bridge never reads, stores, or transmits your recovery seed or private keys outside the device — signing always occurs on the hardware.
- Runs locally: Bridge listens on localhost and does not expose remote network interfaces by default.
Supported platforms & browser notes
Bridge supports modern desktop environments:
- Windows 10 and newer (64‑bit)
- macOS (Intel and Apple Silicon)
- Popular Linux distributions (AppImage or distribution packages may be provided)
Browsers differ in how they handle USB device access. WebUSB and WebHID are supported by some Chromium‑based browsers and Firefox with varying levels of native support. Bridge smooths cross‑browser compatibility for web flows that interact with Trezor Suite or other integrations.
Download & install — step by step
- Navigate to the official Trezor website and open the Bridge download page.
- Select the installer for your operating system and download it.
- Run the installer and follow the prompts. On macOS you may need to allow the app in System Preferences (Security & Privacy) if Gatekeeper blocks it.
- After installation, Bridge typically runs quietly in the background. You may see a tray icon or a small status indicator depending on the OS.
Tip: Keep Bridge updated — newer versions add improved browser compatibility and fixes for edge cases.
How to verify the installer
To avoid tampered installers, verify checksums or signatures when provided:
- On the official download page, look for a SHA256 checksum or PGP signature next to the installer link.
- After downloading, compute the checksum locally (e.g.,
shasum -a 256 filenameon macOS/Linux or use a checksum utility on Windows) and compare it to the published value. - If a PGP signature is published, verify it against Trezor’s official public key following their verification instructions.
If values don’t match, delete the download and obtain the installer again from the official source.
Using Bridge with Trezor Suite and web apps
Once Bridge is running, launching Trezor Suite or accessing a supported web app will typically detect the local service automatically. The connection flow usually looks like this:
- Open the app or web page and select "Connect device".
- The app queries the Bridge service to enumerate available Trezor devices attached via USB.
- When an app or web origin requests access, Bridge enforces permission checks. Grant access only when you recognize the app or URL.
- Confirm transaction details on the Trezor device before signing. The device’s display is the single source of truth for what you’re approving.
Always inspect the origin (domain name) and the permission prompt before granting access.
Troubleshooting common issues
Device not detected
Try these steps in order:
- Reconnect the USB cable and try another port — prefer a direct port instead of a hub.
- Use a different cable that supports data (some cables are power-only).
- Restart the Bridge service or reboot your computer.
- Ensure the device is powered on and unlocked (enter PIN if required).
- On Linux, ensure udev rules are installed if required for device permissions.
Bridge fails to start
Check for OS-level blocks (Gatekeeper on macOS, SmartScreen on Windows). Reinstall Bridge after temporarily allowing the installer, and then re-enable full security checks. Consult local logs (Bridge log files) for error messages to share with support if needed.
Browser cannot access device
Try a supported browser (Chromium-based or latest Firefox) and confirm that Bridge is running. Some browsers require enabling experimental flags for WebUSB; if possible, use the desktop app (Trezor Suite) which uses Bridge directly and avoids browser API inconsistencies.
Security & privacy considerations
Bridge is intentionally minimal: it should never access or store seeds or private keys. Key security guidelines:
- Download Bridge only from Trezor’s official site.
- Confirm checksums/signatures when available.
- Do not run unknown or untrusted browser extensions that may attempt to intercept device communications.
- Review and revoke browser-origin permissions you no longer need.
- Consider using an isolated machine for high-value transactions to reduce exposure to malware on your everyday computer.
Advanced & developer notes
Developers integrating with Trezor Bridge should follow the official SDKs and API references. Important points:
- Respect user consent flows — always request explicit permission before interacting with a device.
- Keep cryptography on-device; never export or reconstruct private keys in software.
- Use recommended libraries to handle USB/WebUSB interactions to avoid subtle security bugs.
For testing, use Trezor’s simulator tools and developer documentation to validate integration behavior across platforms.
Updating & uninstalling Bridge
To update, download the latest installer from the official site and run it — Bridge will replace the previous installation. To remove Bridge, use your OS’s standard uninstall process and restart. After uninstall, verify that no Bridge process remains running and remove any leftover configuration if needed.
FAQ
Do I have to install Bridge to use my Trezor?
For a smooth desktop and web experience, Bridge is recommended. Some modern browser configurations can talk to the device via native WebUSB, but Bridge often improves compatibility and reduces setup friction.
Can Bridge access my recovery seed?
No. Bridge acts as a local proxy and never interacts with seed data. All signing and key storage are handled strictly on the Trezor hardware.
What if I suspect Bridge has been tampered with?
If you suspect tampering, uninstall Bridge, verify that the installer hashes from the official site match your download, and reinstall only from the official Trezor domain. Report suspicious activity to Trezor support and consider moving funds if you believe your environment was compromised.
Best practices summary
- Install Bridge only from the official Trezor website.
- Keep Bridge and device firmware up to date.
- Use data-capable USB cables and connect directly to the computer.
- Verify installer checksums when available.
- Review and manage app/browser permissions regularly.