Overview: Trezor Bridge is the small but essential piece of software that enables your web browser to communicate securely with your Trezor hardware wallet. Without it, modern browsers — which sandbox web pages for safety — cannot reach the USB-connected device directly. Bridge acts as a trusted gateway on your computer, forwarding messages back and forth between your browser (typically a wallet interface such as Trezor Suite or compatible third-party sites) and your Trezor device.
Browsers intentionally limit direct access to local hardware for security reasons. Historically, web apps could use browser plugins or legacy APIs to reach USB devices, but modern browser security models favor fewer and better-audited entry points. Trezor Bridge provides a secure local service that talks to the hardware wallet over USB and exposes a controlled, browser-friendly API via HTTP on the localhost loopback interface. That separation keeps the hardware interaction isolated from web page code while making the device usable from web-based wallets.
Think of Trezor Bridge as a bilingual translator between two worlds:
Bridge runs on your computer as a small background app. When a website wants to talk to your Trezor, it sends requests to Bridge on localhost. Bridge validates and forwards those requests to the physical device, receives the responses, and returns them to the browser. The user still confirms sensitive actions physically on the device (PIN, passphrase, signing transactions), keeping the private keys off the computer at all times.
Installing Trezor Bridge is straightforward and quick. The usual steps are:
Tip: If the browser doesn’t detect the device immediately, restarting the browser or re-plugging the USB cable often resolves the issue. Always use the official installer and distribution instructions to avoid tampered software.
Trezor Bridge is available for common desktop operating systems (Windows, macOS, and many Linux distributions). It’s designed to integrate with modern browsers; most popular browsers will work when Bridge is installed because communication happens via the local HTTP endpoint rather than low-level USB APIs inside the browser. Browser security settings or privacy extensions can sometimes interfere with localhost requests — temporarily disabling strict content blockers for the wallet site is a useful troubleshooting step.
The security model centers on keeping private keys and signature approvals on the Trezor device itself. Bridge only relays structured requests; it does not have access to seed phrases or private keys. Critical safety features:
While Bridge lowers the friction of web-based wallet use, maintaining standard security hygiene on your computer (up-to-date OS, anti-malware, minimal background processes) helps ensure that the local environment remains trustworthy.
If Bridge or your browser can’t see the Trezor device, try the following checklist (from simplest to more involved):
If issues persist, consult official support channels or documentation; include OS version, browser version, Bridge logs (if available), and a brief description of what you tried.
Bridge itself does not send data to external servers; it only connects browser requests to the local device. That said, the websites you use (wallet UIs, explorers, dApps) will observe the addresses and transactions you view or sign. Use trusted wallet interfaces and be mindful when connecting to third-party dApps. If privacy is a high priority, consider routing your Web3 interactions through privacy-preserving services or self-hosted interfaces where feasible.
Developers building integrations should treat Bridge as a local API endpoint that must be called from a secure, user-consented context. Respect origin checks, keep the browser's same-origin and CORS rules in mind, and always prompt users to verify actions on their device. If building open-source tools, provide clear instructions for installing Bridge and handling edge cases such as device resets or multiple connected devices.
For browser-based wallets, yes — Bridge or an equivalent local connector is required so the browser can reach the USB device. Some desktop apps (native clients) communicate directly with the device and do not require Bridge.
Yes when downloaded from official sources. Bridge purposely runs a local-only service and does not contain your private keys. Verify installers with official documentation and checksums when provided.
Yes — Bridge is a local service and any browser on the same machine can call it (subject to browser security rules and permissions).