What is Trezor® Bridge?
Trezor® Bridge is a lightweight background application that enables secure communication between a Trezor® hardware wallet and web-based apps such as Trezor Suite or other compatible clients. Acting as a local intermediary, Trezor® Bridge translates browser requests into USB commands the device understands, while enforcing origin checks and permission prompts that protect users against unauthorized access.
Why Trezor® Bridge matters for security
When you connect a hardware wallet like Trezor®, the connection layer is just as important as the device firmware or the host application. Trezor® Bridge reduces attack surface in three key ways:
- Isolated channel: It creates a controlled, local channel for USB communication rather than relying on direct browser USB access, which can be less predictable across browser versions and platforms.
- Origin enforcement: Bridge mediates which web origins can send commands to your device. This helps ensure only legitimate web apps — for example, Trezor Suite — can request signatures or reveal public data.
- Explicit user consent: Bridge triggers clear user interactions on the Trezor® device before any sensitive operation (like signing a transaction) occurs, keeping the final authorization in your hands.
How Trezor® Bridge works (step-by-step)
The typical flow when using Trezor® Bridge looks like this:
- Your browser requests a connection to a web wallet or Trezor Suite.
- Trezor® Bridge receives the request locally and validates the requesting origin.
- Bridge opens a secured USB session with your Trezor® device and relays commands.
- For sensitive actions — such as exporting a public key or signing a transaction — the Trezor® device displays details and asks you to confirm on-device.
- After confirmation, the device performs the action and returns results through Bridge to the application.
Installation and compatibility
Trezor® Bridge is available for Windows, macOS, and Linux. Installation is straightforward: download the official installer from the Trezor website and follow the platform-specific instructions. Once installed, Bridge runs in the background and is usually updated automatically. For best results, keep your Trezor® firmware and the host application (Trezor Suite or other wallets) up to date.
Common issues and how to fix them
Users occasionally face connectivity problems; most are solvable with a few simple checks:
- Bridge not detected: Ensure the Bridge daemon is running. On some systems you may need to restart your computer after installation.
- Browser warnings: Modern browsers sometimes block local connections or extensions. Try disabling conflicting extensions and ensure your browser is updated.
- Device not recognized: Try a different USB cable or port, and verify the device shows the Trezor® boot screen when connected.
- Permission denied errors: Confirm the web app origin is allowed by Bridge and that no firewall or privacy tool is intercepting local connections.
Security best practices when using Trezor® Bridge
Follow these recommendations to maintain a robust security posture when using Trezor® Bridge:
- Always download Trezor® Bridge and Trezor Suite from official sources. Verify checksums when provided.
- Keep your device firmware updated and review release notes for security fixes.
- Never enter your seed phrase into a computer or browser. Seed entry should be performed only on-device during setup.
- Use the device screen to verify transaction details; do not rely solely on what the web interface displays.
- Limit the number of trusted web origins and periodically review connected sessions.
Alternatives and when to use them
While Trezor® Bridge is the recommended connector for most users, some advanced setups or integrations may use direct communication methods (e.g., WebUSB) or custom tooling. Use these alternatives only if you understand the trade-offs and can verify origin and permission handling. For most users, sticking with the official Bridge + Trezor Suite provides the best balance of convenience and security.
Frequently asked questions
Q: Can malicious websites access my Trezor® through Bridge?
A: No — Bridge enforces origin checks and sensitive operations require on-device confirmation. However, always be cautious and ensure you connect only to trusted web apps.
Q: Does Bridge store any sensitive data?
A: Bridge itself does not store seed phrases or private keys. It facilitates communication; all key operations remain on the hardware device.
Q: Is Bridge open source?
A: Parts of the Trezor ecosystem are open source. Refer to the official Trezor repositories and documentation for details about Bridge's source and audits.
Conclusion
Trezor® Bridge plays a vital role in creating a secure, reliable connection between your hardware wallet and desktop web applications. By mediating requests, enforcing origin checks, and ensuring on-device confirmations, Bridge helps keep your keys safe while preserving the convenience of modern web wallets. Keep Bridge and your device firmware updated, follow the security best practices outlined above, and rely on official software to minimize risks.