Trezor Bridge® is the official secure gateway between your Trezor hardware wallet and modern web browsers or applications. It acts as a local proxy service that securely translates commands from browser-based wallet interfaces to your Trezor device, ensuring your private keys never leave your hardware wallet. Without Bridge, many modern browsers can’t directly interface with USB devices or WebUSB, so Bridge becomes essential for usability and security.
This page presents a detailed but readable explanation of Trezor Bridge, its architecture, its role in the crypto ecosystem, and also draws contrasts/mentions with Ledger tools such as Ledger.io/start, Ledger Login, Ledger Suite, Ledger Io Start, Ledger Bridge, and Ledger hardware wallet integration, to help readers familiar with both ecosystems.
Once installed, Trezor Bridge runs on your computer as a background service (daemon). It listens on a local endpoint (e.g. localhost) for HTTP or WebSocket requests from wallet apps or browser frontends. Those requests are translated into USB (or WebUSB) commands that the Trezor device understands. When the device responds, Bridge relays the response back to the caller. In effect, Bridge isolates your browser from USB hardware and ensures safe communication.
A wallet interface will request to open a session with the Trezor device. You must approve this on the device itself (via PIN or physical button). Only once authorized, the Bridge will forward allowed actions (like read public keys, request transaction signing) to the hardware. Each request is validated and must match user confirmations.
When you initiate a transaction (e.g. sending crypto, interacting with a smart contract), the wallet frontend sends the transaction data (unsigned) via Bridge. The Trezor device displays the transaction details on-screen, you approve or reject, and if approved, Trezor signs internally and returns the signed payload to Bridge, which relays it back to the web app or wallet.
Popular wallet apps like Trezor Suite or decentralized apps (dApps) integrate with Bridge by calling a Trezor Connect API that internally routes through Bridge. Because Bridge abstracts USB/WebUSB, the web apps do not need native browser plugins or extensions. Bridge maintains compatibility across browser changes and OS updates.
Trezor Bridge is built with security-first principles. Its core mission is to ensure **your private keys never leave the device** and that all operations require device confirmation. Here are key security features:
The Bridge only relays commands and responses. It never knows or stores your seed phrase or private keys. All signing happens within the hardware. Even if malware were to exploit your browser, it cannot make unauthorized signing requests without your confirmation.
Bridge ensures that only properly formatted requests matching expected APIs are processed. Web apps cannot arbitrarily access USB unless allowed by user-approved sessions. This helps mitigate cross-site or malicious script attacks.
Official Bridge installers are digitally signed, and the Bridge version often enforces checksum or signature verification to prevent tampering. Users should always download from the official source (e.g. via Trezor’s official site) to avoid malicious clones.
Bridge runs with only the permissions required (USB access, local binding) without extra privileges. It avoids broader system access, reducing risk surface.
Trezor Bridge supports common operating systems such as Windows, macOS, and Linux. It works with modern browsers (Chrome, Firefox, Edge, Brave) that support local HTTP / WebUSB interactions. Because Bridge runs independently of browser version, it adapts as browsers evolve.
If you use the **Trezor Suite (desktop app)**, it can directly communicate with the device without Bridge in many cases. But for browser‑based interactions, dApps, or third-party wallet frontends, Bridge is usually required. In contrast, Ledger’s ecosystem uses different tools: for example, one might go to **Ledger.io/start** to begin onboarding, use **Ledger Login** authentication, access features through **Ledger Suite**, or engage **Ledger Bridge** when interfacing with web layers, along with **Ledger hardware wallet** itself for security.
While people often compare Trezor Bridge and Ledger Bridge, these are separate systems. You cannot mix them directly. A Trezor device expects Bridge in its ecosystem; a Ledger device expects Ledger’s tools. Still, understanding both helps if you switch or compare features.
In many cases, yes—if you interact with wallet apps or dApps in your browser, Bridge is needed to allow the interface to detect and communicate with the hardware device. If you use the native Trezor Suite desktop application, Bridge may not be required for certain operations, though it often enables broader compatibility.
Always download Bridge from Trezor’s official domain or documentation (for instance via links on Trezor.io/start or the official docs). Use signed installers, verify checksums if available, run the installer, then restart your browser. Avoid third‑party mirror sites.
They operate independently. You should not try to combine them for the same device. Use Trezor Bridge only with a Trezor device, and for Ledger, use **Ledger Bridge** or the official Ledger software chain (via **Ledger.io/start**, **Ledger Login**, **Ledger Suite**). Mixing may lead to compatibility or security issues.
If Bridge malfunctions, your browser wallet will not detect your Trezor. Troubleshooting steps include: reinstalling Bridge, updating version, restarting computer and browser, ensuring no firewall blocks localhost, and verifying that no conflicting USB‑driver software is interfering.
Yes, many decentralized applications or web wallets integrate with Trezor Connect which uses Bridge under the hood. As long as you approve the session and transaction on your hardware, you can use these apps safely.