Trezor Bridge is a lightweight background service developed by the Trezor (SatoshiLabs) ecosystem that acts as a secure intermediary between your Trezor hardware wallet and web or desktop applications. It enables communication between your device and compatible applications via USB (or other supported protocols) while preserving the integrity of your private keys and ensuring that no sensitive key material ever leaves the hardware device itself. :contentReference[oaicite:0]{index=0}
Historically, web browsers restricted direct hardware access for security reasons. Trezor Bridge was introduced to fill that gap: instead of relying on browser extensions or special APIs, Bridge runs locally on your computer and exposes a safe, minimal interface that applications can invoke. :contentReference[oaicite:1]{index=1}
Once installed, Trezor Bridge runs as a background service (daemon) on your machine. It typically listens on a local loopback address (for example, `http://127.0.0.1:21325`) to accept secure requests from authorized apps. :contentReference[oaicite:2]{index=2}
When a browser or application needs to interact with your hardware wallet (e.g. to fetch your public addresses, sign a transaction, or show a message to approve), it sends a request to Bridge. Bridge, in turn, relays that request to the Trezor device over USB (or other supported transport), waits for the user to confirm the action on the device, and then returns the response back to the calling software. :contentReference[oaicite:3]{index=3}
Importantly, Bridge never handles or stores your private keys or seed phrase. Its job is purely to manage communication and enforce request boundaries. :contentReference[oaicite:4]{index=4}
Here is a step-by-step guide to getting Bridge set up and connecting your hardware wallet:
Once Bridge is running and connected, your everyday crypto tasks become seamless:
Each action that involves custody or key usage is routed through Bridge and must be confirmed physically on your Trezor device. This ensures that even if malicious software is present on your computer, it cannot spontaneously send transactions without your consent. :contentReference[oaicite:19]{index=19}
In recent development updates, Trezor has gradually shifted toward **native browser protocols** (WebUSB / WebHID) and the modern **Trezor Suite** architecture for most use cases, reducing reliance on a standalone Bridge installation. :contentReference[oaicite:20]{index=20}
As a result, the standalone Bridge is considered by some as a legacy component for backward compatibility. Users are encouraged to prefer the desktop Suite or modern browser-native flows when possible. :contentReference[oaicite:21]{index=21}
Here are some typical problems users face and suggestions to resolve them:
If problems persist, consider removing the Bridge installation and re-installing fresh, or switching to the desktop Trezor Suite which typically handles communication internally. :contentReference[oaicite:27]{index=27}
Security remains the top priority in Trezor’s architecture. Bridge does not have access to your private keys or seed phrase. Every sensitive operation must be confirmed on the physical Trezor device. :contentReference[oaicite:28]{index=28}
Still, you should follow best practices:
Trezor Bridge has played a vital role in bridging the gap between web-based crypto apps and secure hardware wallets. By facilitating safe, local-only communication, it makes it possible for browsers and apps to interact with the Trezor device without exposing private keys.
Although modern browser APIs and the evolution of Trezor Suite reduce reliance on a standalone Bridge, it remains useful in backward compatibility scenarios or for legacy integrations. In either case, the security model is robust: as long as you follow best practices and verify authentic software sources, Bridge offers a trustworthy connectivity layer.
If you're building a web app that supports hardware wallets, consider using Trezor Connect or the latest recommended integration methods. For end users, using Trezor Suite desktop or native browser flows is often the easiest and safest path forward.