Introduction
What is Trezor Bridge?
Short definition
Trezor Bridge is a lightweight desktop application that acts as a secure communication layer between your web browser and a Trezor hardware wallet. It replaces older direct web-USB methods and simplifies interacting with web apps—while maintaining separation between the local machine and the hardware device to reduce attack surface.
Why it matters
By managing USB communications and protocol handling, Bridge enables wallet software and browser-based interfaces to talk to your hardware wallet in a reliable, consistent, and secure manner.
Design & Architecture
How Bridge fits in the stack
Trezor Bridge runs locally and exposes a small HTTPS-like API for web interfaces to send commands. The architecture isolates the hardware interaction from the browser runtime, enabling cross-browser compatibility and providing a controlled, signed channel for messages.
Core components
• Bridge daemon: runs in the background, listens for local API calls.
• USB layer: handles device detection, secure USB transactions.
• Authentication & handshake: ensures only authorized apps can talk to a connected device.
Security model
Principles
Trezor Bridge follows a minimal trust approach: it does not store private keys or seed phrases. All cryptographic signing happens on the hardware device itself. Bridge is strictly a transport — it conveys requests and responses while adding protections such as origin verification and user confirmation prompts on the device.
Threat reduction
Key threats mitigated by Bridge include browser-based exploitation, corrupted web pages attempting silent transactions, and ambiguous device selection when multiple USB devices are connected.
Installation & Setup
Step-by-step
Installing Trezor Bridge is straightforward: download the installer from the official Trezor site, run it, and grant any required permissions. Once installed, Bridge launches automatically and remains ready to mediate browser connections. Most wallets detect Bridge automatically; otherwise enable browser integration per wallet instructions.
Platform notes
Bridge supports Windows, macOS, and major Linux distributions. Keep it up to date — updates can include security fixes and compatibility improvements with new browsers or operating system changes.
User experience
How interactions look
When you initiate an operation (e.g., sign transaction, export address), your wallet app sends a request to Bridge, which forwards it to the device. The device will present transaction details on its screen and require you to confirm via physical buttons. This protects against remote manipulation or hidden transactions.
Visual cues
Always inspect the hardware device’s screen for amounts, addresses, and details. Bridge cannot override the device’s UI and shows only connection status on the computer side.
Best practices
Keep your device and Bridge secure
• Always download Bridge from the official source.
• Use the latest stable OS and browser versions.
• Verify firmware updates on the device screen and confirm them physically.
• Never enter recovery seeds into a computer; use the device-only recovery flow.
Network hygiene
Avoid using public or untrusted computers for critical operations. Where possible, use an air-gapped approach for seed generation and maintain strong endpoint security on your workstation.
Troubleshooting
Common issues & fixes
• Device not detected: replug USB, check cable, restart Bridge daemon.
• Browser says "No compatible device": confirm Bridge is running and up to date; allow site permissions.
• Multiple devices: ensure you select the correct Trezor model from the wallet UI and confirm fingerprints on the device.
When to seek support
For persistent connectivity problems, produce diagnostics logs and consult official support channels rather than third-party guides to avoid misinformation.
Compatibility & integrations
Wallets and services
Trezor Bridge is intentionally compatible with many third-party wallets and dApps that support hardware wallets. Bridge provides a stable API surface, so integrators can rely on consistent device discovery, session handling, and message passing.
Developer notes
Developers building integrations should use the official libraries and follow recommended origin checks and user prompts—never bypass device confirmations in code.
Privacy considerations
What Bridge does and doesn’t do
Bridge does not harvest or store private keys, addresses, or transaction contents beyond transient in-memory buffers needed to forward requests. However, endpoint privacy depends on the wallet app and network being used—consider connecting through privacy-enhancing networks or using coin-specific privacy tools if necessary.
Auditability
Bridge’s codebase and update history are intended to be auditable; rely on official project channels for release notes and verified binaries.
Conclusion & next steps
Final summary
Trezor Bridge is the practical, secure bridge between browser-based wallet UI and the hardware-level protections of a Trezor device. It centralizes USB handling, improves cross-browser compatibility, and reinforces the user-confirmation model that makes hardware wallets fundamentally safer than hot storage.
Recommended next steps
• Install Bridge from the official source and verify signatures where offered.
• Keep your device firmware and Bridge up to date.
• Always confirm actions on the device screen before approving transactions.