Your definitive walkthrough to install, use, and secure Trezor Bridge
Trezor Bridge is a lightweight local service (daemon) that acts as a secure intermediary between your browser or wallet application and the Trezor hardware device. Because modern browsers often restrict direct USB access, Bridge bridges that gap and ensures reliable, encrypted communication without exposing your private keys to the host environment.
Essentially, Bridge serves as a translator: your wallet software sends commands to Bridge, Bridge relays them over USB to your Trezor, and then passes responses back. This model preserves the device’s security boundary: **the private keys never leave your Trezor**.
Bridge is available for **Windows**, **macOS**, and **Linux** distributions (e.g. Debian, Ubuntu, Fedora). Choose the package that matches your OS version. On many platforms, the Bridge runs as a background service after installation.
Download the `.exe` or `.msi` installer, run it with admin privileges, accept the license agreement, and finish the installation. The Bridge service should auto-start. If not, you may need to explicitly launch it or set it to auto-run.
Open the downloaded `.dmg`, drag the Bridge app into your Applications folder, and launch it. Grant any necessary USB access permissions under “Security & Privacy” if prompted.
Use the `.deb` or `.rpm` package for your distribution (or compile from source). For example, under Debian/Ubuntu:
sudo dpkg -i trezor‑bridge‑x.x.x.deb
Then start the service with `systemctl start trezor-bridge` or `trezor-bridge &`.
After installation, you should see the Bridge process running, and your browser or wallet app should detect “Bridge enabled” or “Trezor connected.” If it doesn’t, check firewall or USB permissions to allow local (loopback) connections.
Bridge listens on a local port (e.g. `localhost:21325`) and awaits JSON‑RPC or command calls from a client (e.g. Trezor Suite, web wallet). It validates the origin, applies whitelisting, serializes the command, sends it over USB to the Trezor device, receives the response, verifies integrity, and relays it back to the client.
Bridge ensures that only authorized applications can issue commands. Unknown or malicious clients are blocked. Each request is validated against the expected API signature, preventing malformed or tampered commands from reaching the hardware device.
It’s worth noting that the standalone Bridge architecture is being gradually deprecated in favor of an integrated communication layer inside **Trezor Suite**. But many browser‑based workflows and legacy setups still rely on standalone Bridge. (If using Suite, the Bridge module is often bundled internally.)
- **Private keys remain on-device**: Bridge never sees or stores them. - **Local-only listening**: Bridge listens only on `localhost` (no external access). - **Signed updates**: Update packages are cryptographically signed by Trezor / SatoshiLabs. - **User confirmation required**: Any signing or sensitive actions must be confirmed physically on the Trezor device.
Always download Bridge from the **official Trezor site**, verify checksums or digital signatures, and avoid third‑party mirrors. Keep Bridge, your firmware, and wallet apps up to date. Use a trusted computer and firewall rules to avoid blocking Bridge. When approving transactions, carefully inspect addresses and amounts shown on the Trezor screen rather than relying on the UI display.
- If Bridge is not detected, try restarting your system or the Bridge service. - Switch USB ports or use a different cable. - On macOS, permit USB access under system settings. - On Linux, check udev rules or device permissions. - Remove conflicting drivers or older Bridge versions before reinstalling.
1. Do I always need Trezor Bridge to use my hardware wallet?
Not always. Some modern browsers and operating systems support **WebUSB / native USB access** and can communicate directly to your Trezor device. However, Bridge ensures broader compatibility, resolves edge cases, and handles OS quirks. In web‑based workflows, Bridge is still often required for seamless connectivity.
2. Can Bridge ever see or steal my private keys or seed?
No. Bridge acts solely as a message transport layer. All key operations (signing, deriving) happen inside the Trezor device itself. Bridge never stores or accesses private keys or seeds.
3. How do I uninstall or remove Bridge?
Use the standard uninstallation mechanism of your operating system (e.g. Control Panel on Windows, `dpkg -r` on Linux, or drag-to-trash + cleanup on macOS). After removal, web wallet connectivity may fail unless you use native USB / WebUSB.
4. What if Bridge isn’t detected by my browser?
First, ensure the Bridge service is running. Next, check firewall or security software is not blocking localhost ports. Try reloading or restarting your browser. Also, ensure permissions for USB / HID are granted. In some systems, a reinstallation (after fully removing old versions) resolves the issue.
5. Is there a difference between Trezor Bridge and Trezor Suite’s integrated communication?
Yes. Trezor Suite (desktop app or integrated web Suite) includes internal device‑communication modules, reducing the need for separate Bridge installs. Standalone Bridge is gradually being deprecated in favor of this integrated model. If you use Suite, the communication layer is already bundled and managed automatically.