What is Trezor Bridge?
Trezor Bridge runs on your computer and exposes a secure local API that wallet applications use to communicate with your Trezor. Where web browsers restrict direct USB access for security reasons, Bridge provides a controlled gateway so that web apps can request signatures, public keys, and device metadata without compromising your private keys.
Core responsibilities
- USB mediation: safely manage USB connections to Trezor devices and avoid accidental device access.
- Message routing: forward structured requests from apps to the device and deliver signed responses back to the caller.
- Permission gating: ensure that operations require explicit user approval on-device.
- Compatibility: keep older and newer Trezor firmware working with modern web apps and native wallets.
Why Bridge matters
Hardware wallets isolate private keys from networked systems. Bridge fills the usability gap between that strong isolation and the convenience of software wallets. Without Bridge (or a browser with direct WebUSB access), web apps would be unable to talk to your Trezor. Bridge ensures that conversation is secure, explicit, and as transparent as possible.
Security-first design
Bridge minimizes privileges and avoids retaining long-lived credentials. All sensitive operations — including signing — must be verified on the Trezor device physically.
Privacy-preserving
No private keys or seed material ever leave the device; Bridge only transmits non-sensitive requests and signatures.
How to install and set up
Bridge supports Windows, macOS, and Linux. The installation process is straightforward and takes a few minutes.
- Download Trezor Bridge from the official Trezor website. Verify the download checksum if available.
- Run the installer and follow on-screen instructions. On macOS you may need to allow the app in System Preferences > Security & Privacy.
- Restart your browser (if using web wallets) after installation to ensure the new local API is detected.
- Connect your Trezor device with a known-good USB cable. Grant permission on the device when prompted for any interaction.
Tip: prefer the original cable that came with the device or a high-quality data cable. Faulty cables are a common source of connectivity problems.
Security best practices
Bridge is an important part of a secure workflow, but your overall security depends on several complementary practices:
- Keep firmware updated: always update your Trezor's firmware using the official updater to get the latest security fixes.
- Verify downloads: obtain Trezor Bridge installers only from the official Trezor domain and verify signatures or checksums where provided.
- Use a trusted host: don't install Bridge on shared or untrusted machines where others can access your session.
- Check addresses on-device: when approving transactions, always verify the recipient address and amount on the Trezor screen — not the computer screen.
- Back up your recovery seed: store it offline in multiple secure locations. Never take a digital photo of your seed.
Common troubleshooting
Connectivity issues are usually resolvable by following a few simple steps.
- Restart Bridge and your browser: close the Bridge process and relaunch; then restart the browser to clear stale connections.
- Try another USB port or cable: use a different port (avoid hubs) and a good-quality cable.
- Reinstall Bridge: uninstall, download the latest version from the official site, and reinstall.
- Check OS permissions: on macOS allow access in Security & Privacy; on Linux ensure udev rules are installed.
- Device recovery mode: if the device is unresponsive, follow the official recovery instructions — do not enter your recovery seed on a computer unless explicitly required and verified.
FAQ
Does Bridge see my seed?
No. Bridge never has access to your recovery seed or private keys. It only forwards structured requests and signed responses between host apps and the device.
Do I need Bridge for every wallet?
Most browser-based wallets and many native apps expect Bridge or direct USB/WebUSB access. Some wallets include native integrations that bypass Bridge; always follow the wallet's guidance.
Is Bridge open source?
Parts of the Trezor ecosystem are open source. Check the official repositories for the most up-to-date licensing and source code information.