Trezor Bridge — The Secure Gateway to Your Hardware Wallet

Overview

Trezor Bridge is the secure communication layer that enables your Trezor hardware wallet to talk with desktop applications and web interfaces. As a small, trusted background service, Bridge handles low-level USB/transport interactions, providing a stable and secure API surface for Trezor Suite, third-party wallets, developer tools, and browser integrations. The Bridge acts as the secure gateway that mediates device access, permission prompts, and firmware checks so that private keys remain protected within the hardware device.

How it works

Trezor Bridge runs locally on a user’s machine and exposes a controlled interface for applications to request device actions (like retrieving addresses or signing transactions). It supports common transports such as WebUSB, WebHID, and native USB/HID channels. Bridge ensures only permitted clients can send requests, manages reconnection logic, and verifies firmware signatures when necessary. This architecture reduces attack surface and improves user experience by standardizing the connectivity stack across operating systems.

Core responsibilities

• Device discovery: Find connected Trezor devices and report state.
• Secure transport: Provide an encrypted and authenticated channel to the device.
• Permission handling: Broker user consent flows for web and desktop apps.
• Firmware checks: Help verify firmware authenticity and update availability.
• Compatibility: Offer consistent APIs across Windows, macOS, and Linux.

// Example pseudocode: request an address via Bridge
fetch('http://127.0.0.1:21325/bridge/api', {
  method: 'POST',
  body: JSON.stringify({method: 'getAddress', params: {path: "m/84'/0'/0'/0/0"}})
}).then(r => r.json()).then(console.log);

Security model

The design principle of Trezor Bridge is simple: keep secrets inside the hardware device. Bridge never stores private keys. It only forwards well-formed commands and returns signed responses. It is important that users always download Bridge from official channels, verify checksums/signatures, and keep the service updated. Trezor Bridge also includes anti-tampering checks and encourages users to validate device firmware through the accompanying Suite UI.

For developers

Developers can integrate with Bridge using HTTP/JSON endpoints or the provided SDK wrappers. Bridge simplifies development by hiding platform-specific USB quirks and offering a predictable API for signing flows, address derivation, and device metadata. When building integrations, follow these best practices:

• Use origin checks and strict Content Security Policies for web clients.
• Limit request scope — request only the operations you need and prompt the user when appropriate.
• Use signed Release bundles for libraries that interact with Bridge.
• Log minimal telemetry; never include sensitive data.

Download & installation

Always download Trezor Bridge from the official Trezor website. Installer packages are available for Windows, macOS, and Linux. After installation, Bridge will run as a background service and show a small status indicator. The Official page also contains verification instructions—compare SHA256 checksums and PGP signatures to ensure you have an authentic installer.

5 Frequently Asked Questions