Official Secure Gateway for Hardware Wallets
Welcome to the official guide for Trezor Bridge® — the secure communication layer between your Trezor device (hardware wallet) and your computer or browser. Its mission is to reliably and safely bridge the communication gap, ensuring that no malicious software can intercept, tamper, or mislead you during your crypto operations.
In this document, you’ll learn what Trezor Bridge is, how it works, how to install and configure it, security practices, troubleshooting, versioning, and best practices. Use this as your reference whenever you’re working with Trezor in environments that require bridging (rather than direct connection via browser or WebUSB).
Trezor Bridge® is a background application (daemon/service) that runs on your computer and acts as a secure intermediary between your Trezor hardware wallet and web interfaces (or desktop applications) such as Trezor Suite or browser-based tools. It enables safe, consistent communication over USB by using well-defined APIs and encryption protocols.
Because direct access to USB hardware from browser environments can be restrictive, inconsistent across platforms, or insecure, Bridge smooths that gap. It normalizes device communication, abstracts OS-level quirks, and guards against intrusive software or drivers that might interfere.
Trezor Bridge is actively maintained by the Trezor team, with regular updates for compatibility, performance improvements, and security patches. It is the officially endorsed gateway to ensure your interactions with your hardware wallet are robust and safe.
Modern browsers and operating systems impose strict constraints on accessing USB devices directly. These security boundaries protect users from arbitrary hardware access, but they also complicate how the wallet and host software communicate. Bridge provides a safe, consistent channel that works across Windows, macOS, Linux, and other supported OSes.
By sitting between browser/app and hardware device, Bridge limits exposure: it verifies the origin of requests, ensures only permitted commands pass, and enforces cryptographic signatures. This minimizes risks from malware, browser extensions, or rogue processes attempting to misuse your Trezor.
Not all USB stacks or WebUSB implementations work consistently across platforms. Bridge handles platform-specific drivers, permissions, and peculiarities so that the wallet software doesn’t have to. Users enjoy a more consistent and smoother UX.
Some features—especially those that require more advanced device APIs or low-level control—are more reliably enabled through Bridge. These include firmware upgrades, advanced device settings, passphrase handling, and future enhancements.
Use modern supported browsers (Chrome, Firefox, Edge). Ensure your OS is up to date and that antivirus/anti-malware tools do not block Bridge operations.
To install, go to the official Trezor website or your device setup flow and download the version appropriate for your OS. Always use the link from a trusted domain (such as trezor.io/bridge or via Trezor Suite). Avoid links from third parties or unknown sources.
Once installed, Bridge will run silently in background (as a service/daemon). It listens on a local interface (e.g. `localhost:21324`, or similar) to accept requests from authorized client software.
When Trezor Suite or other host software launches, it auto-discovers Bridge and establishes a secure channel. You may see “Bridge detected” or “Connect device via Bridge” in the UI.
Allow Bridge through your firewall (if needed), and permit the client app to communicate with it. You may also add exceptions or rules so Bridge isn’t blocked by OS-level protections or security suites.
Bridge uses a well-documented, serialized API to forward JSON‑RPC or binary commands from the host software to the device, and vice versa. Each command is validated, origin checked, and passed only if safe. Responses are likewise signed and checked.
Only registered and recognized host software (Trezor Suite, approved apps) are permitted to interface with Bridge. Unknown or malicious programs are blocked or ignored. This “whitelisting” ensures only trusted clients can talk to your hardware device.
All traffic between the host and Bridge, and between Bridge and device, is integrity-protected. Bridge ensures that data is unmodified in transit, and uses cryptographic checks to guard against tampering or injection attacks.
Bridge updates are cryptographically signed by the Trezor maintainers. The installation process verifies signatures before applying upgrades. Never accept or install a Bridge update from an unsigned or unverified source.
Most host software (Trezor Suite) will display the currently installed Bridge version. You may also invoke a command-line argument or a built-in “About” dialog.
Bridge will often prompt you when an update is available. Always use the “Check for update” function built into trusted software or download from the official site. Never install manually from unknown sources.
The Bridge maintainers strive to maintain compatibility across versions so that newer Bridge will work with slightly older clients and devices. However, in rare cases, very ancient clients or devices may require matching or legacy Bridge versions.
If an update causes issues, some platforms let you revert to a previous (stable) Bridge version. Do this only if directed by Trezor support, and always backup before changes.
If your wallet software says “Bridge not found,” check that Bridge service is running. On Windows or macOS, reboot. On Linux, verify the daemon is active. Also ensure firewall or security software isn't blocking Bridge’s local port.
Try a different cable or USB port. Avoid USB hubs or extension cables, which can introduce issues. On some systems, USB power or compatibility can be inconsistent.
On macOS, you may have to grant “Full Disk Access” or “USB Device” permissions to Bridge or your host client. On Linux, ensure your user has rights to access the USB bus (e.g. via udev rules).
Redownload the installer from the official site, uninstall the old version fully, and reinstall. Don’t resume or continue partial installations. Clear cache or temp files if needed.
Check logs (Bridge often logs to system or user log files). Check if other software is conflicting (security tools, USB monitors). Restart the machine and retry. If persistent, contact Trezor support with logs.
Ensure your Trezor Suite or web client version supports the installed Bridge version. If there’s a mismatch, upgrade the client or install a compatible Bridge version as recommended by official documentation.
Developers interested in integrating with Trezor Bridge can review the public API/SDK documentation (often in the Trezor GitHub or dev docs). The API describes command formats, responses, error codes, and allowed operations.
You may build your own host application (desktop or web) that connects to the Bridge. When doing so, you must register your app (or verify its origin) and adhere to the security model to avoid being blocked. Unauthorized or rogue apps should never be able to interact with the device.
Bridge includes logging capabilities. Developers or advanced users may turn on verbose logging to diagnose issues. Logs typically contain timestamps, commands, errors, and internal status. Be careful not to leak sensitive information in logs.
Bridge is generally open source (or has open components). You can review its code, propose fixes, or audit it. Many security researchers and community contributors help ensure that Bridge remains trustworthy and robust.
Trezor Bridge® is a vital piece of infrastructure that ensures your hardware wallet can communicate safely and reliably with your computer or browser. By abstracting platform differences, enforcing origin checks, and securing the data channel, Bridge adds a significant security layer to your crypto operations.
Always use the official Bridge versions, keep everything updated, and adhere to best practices. Combine Bridge with careful device handling (PIN, seed storage, passphrases) to protect your crypto assets.
If at any point you encounter issues, consult the official support, user documentation, or community forums — but never compromise security by installing unverified software or giving up your recovery seed.