Tŕezor™ Bŕridgeʬ — Securing℗ Your Digital Assets©

Overview — What is Trezor Bridge?

Trezor Bridge is a lightweight connectivity application that enables secure communication between your Trezor hardware device (Trezor One, Trezor Model T, or compatible variants) and applications running in your web browser or on your desktop. It acts as a local bridge: instead of exposing your device directly to the internet, your browser talks to the Bridge over a local, authenticated channel, and Bridge forwards signed requests to the hardware wallet via USB (or WebUSB where supported).

In practical terms, Trezor Bridge simplifies setup and interaction: it provides a consistent API surface for wallets, decentralized apps, and developer tools while keeping your private keys safely inside the secure hardware.

Installing Trezor Bridge — step by step

This section describes the canonical installation flow for the major platforms. If you’re integrating into a secure environment (enterprise, kiosk), follow additional IT governance about code signing, allowed executables, and firewall rules.

Windows

1. Download the Windows installer from the official source. Always verify the URL and checksum where available.
2. Run the installer and accept the prompts. The Bridge installs a small background service and registers a local HTTP endpoint used by browser extensions and apps.
3. After installation, connect your Trezor device via USB. Open your browser wallet or Trezor Suite and follow the on-screen prompts.

macOS

1. Download the macOS DMG and open it.
2. Drag the Bridge application to your Applications folder and run it.
3. macOS may prompt for permission to access USB devices; approve those prompts.
4. Connect your Trezor and proceed in your browser or Suite.

Linux

Linux distributions vary. Bridge is distributed as a .deb, .rpm, and as a generic AppImage or binary for some distros.

1. Install the package using your package manager (for Debian/Ubuntu: sudo dpkg -i trezor-bridge.deb).
2. Ensure the udev rules are installed so non-root users can access USB devices.
3. Restart the Bridge/daemon if required, then connect your device.

Tip: the Trezor Suite application bundles the necessary connectivity for many users. If you prefer a single app, use Suite instead of standalone Bridge.

Security model and privacy

Trezor Bridge is designed as a forwarder: it does not hold private keys, seed phrases, or long-term credentials. Its main security responsibilities are:

• Authenticated local communication: Bridge exposes a localhost interface that requires origin validation and, where possible, handshakes to prevent unauthorized clients from talking to your device.
• Limited permissions: It only forwards structured signing and information requests; sensitive approvals always require user confirmation on the hardware device itself.
• Minimal telemetry: Official Bridge releases aim to minimize telemetry and do not transmit seed data. Always check privacy settings and release notes for changes.

Threat model — what Bridge protects against

Bridge helps mitigate threats that arise from direct USB access and browser limitations:

• Prevents rogue web pages from directly accessing USB without user consent.
• Limits the attack surface by centralizing connectivity logic into a single, signed binary rather than ad-hoc drivers.
• Ensures the user must verify addresses, amounts, and actions on the physical Trezor device — an essential out-of-band confirmation step.

What Bridge does not protect against

• It does not protect a compromised host machine; if your computer is infected with malware that intercepts screen content or keystrokes, additional defenses are required.
• It cannot stop social engineering — never reveal your recovery seed to anyone claiming to be support.

Developer integration & APIs

Trezor Bridge exposes a set of RPC-style endpoints and a standard JSON API used by Trezor Suite and many third-party wallets. If you are building an application that integrates with Trezor, keep these principles in mind:

• Use established libraries: Use official trezor-connect or maintained SDKs rather than implementing USB protocols from scratch.
• Origin checks: Always verify request origin and implement user-consent flows — prompt users clearly when requesting signatures.
• Graceful failure: Design flows to handle device disconnects, firmware update prompts, and user rejections.

Typical integration flow

1. Application calls the Bridge API (via trezor-connect library).
2. Bridge checks the request origin and forwards the command to the Trezor device.
3. The device displays the details (address, amount, operation) and requests a physical confirmation.
4. On approval, the signed payload is returned to the application through Bridge.

Developers: sign your application and instruct users to only download Bridge and apps from official sources. Document user actions clearly so they can verify what they sign on the device.

Day-to-day workflows with Trezor Bridge

Most users have a handful of recurring tasks that involve Bridge. Here are concise guides to the most common ones.

Adding an account / checking a balance

1. Open your browser wallet or Trezor Suite.
2. Connect the Trezor device; Bridge will expose the device to the app.
3. Add the account; the application will query public addresses via the device.
4. Balances are calculated by the wallet using blockchain queries; private keys remain on the device.

Sending crypto

1. Create a transaction in your wallet app and enter the recipient and amount.
2. Review the transaction details in the app and wait for the Trezor device to request confirmation.
3. Check the address and amount on the device screen exactly (not just in the app) and approve by pressing the device buttons.
4. The signed transaction is returned to the wallet and broadcast to the network.

Performing firmware updates

When a firmware update is required, the Suite or web app will prompt you. Firmware updates improve security but must be performed cautiously:

• Always confirm the update within the official Trezor Suite or official site instructions.
• Ensure you have your recovery seed securely stored before updating.

Troubleshooting & common issues

Connectivity issues are the most-common Bridge-related support requests. The following checklist resolves the majority of cases:

Bridge not detected by browser

• Verify Bridge is running (check system tray / activity monitor).
• Restart Bridge and the browser.
• Ensure no other USB application is locking the device (close other wallet apps).
• On Linux, confirm udev rules are installed and the user has USB permissions.

Device disconnects randomly

• Try a different USB cable or port — cheap/long cables can cause power or data issues.
• Disable USB power management features that may suspend the connection.
• Test the device on another machine to isolate hardware from software problems.

Browser shows a security prompt

Modern browsers will show a permission dialog for USB access or localhost connections. These prompts are expected; follow them and verify the origin before granting access.

Still stuck?

If the issue persists, consult the official support knowledge base or export logs for diagnostics. Avoid sharing your recovery phrase with support — legitimate support will never ask for it.

Frequently asked questions

Do I always need Bridge to use my Trezor?

Not always. Trezor Suite bundles the necessary connectivity and may be used without a separate Bridge install. Web-based wallets and some browser extensions, however, rely on Bridge or WebUSB to communicate with devices.

Is Bridge safe to run on my machine?

Bridge itself is a signed, minimal service with a specific, local purpose. Use only official releases and verify signatures when possible. The security of your machine remains important: keep your OS and antivirus updated and avoid untrusted software.

Can multiple apps access my Trezor through Bridge at the same time?

Typically, only one client should actively control the device at a time. Simultaneous access may cause conflicts. If you need multiple clients, connect and disconnect cleanly between sessions.

What about WebUSB — can I skip installing Bridge?

Some browsers support WebUSB which allows direct access without Bridge, but compatibility is not universal. Bridge ensures a more consistent experience across browsers and operating systems.

Best practices & security checklist

1. Download Bridge only from the official domain and verify checksums when provided.
2. Always verify transaction details on the Trezor device display before approving.
3. Store your recovery seed offline, in a secure physical location; never type it into a website.
4. Keep your host computer clean: update OS, run reputable antivirus, and avoid installing untrusted browser extensions.
5. When in doubt, use Trezor Suite — it bundles connectivity, updates, and support in a single, maintained app.

Legal, privacy & support notes

This document provides general informational guidance. Trezor Bridge and any references to Trezor products are trademarks of their respective owners. For precise, up-to-date information about releases, vulnerabilities, or legal notices, always consult official channels and support pages.

Support resources and the knowledge base contain step-by-step articles, verified downloads, and troubleshooting utilities. When contacting support, never share your recovery phrase or private keys; legitimate support staff will not request them.