The Alby lightning-browser-extension is an open-source, MIT-licensed Bitcoin Lightning browser extension that exposes a WebLN wallet interface to multiple Lightning nodes and acts as a key signer for Nostr, Liquid and onchain use, built for people who want Lightning payments and authentication to happen inside an ordinary web browser.

What it is

It is a lightweight web extension written in TypeScript that brings the Bitcoin Lightning Network into websites, enabling both payment and authentication flows. Alby implements the WebLN standard, giving pages a universal, programmatic interface to connect to Lightning Network nodes and to request payments, invoices, signatures and logins. It runs in all Chromium-based browsers (Chrome, Edge, Opera, Brave) and in Firefox desktop and mobile, and it implements LNURL-pay, LNURL-auth and LNURL-withdraw alongside keysend payments sent without an invoice. Multiple accounts are supported across different node backends, including LND, CLN and custodial options, so the same extension can front either a custodial or a non-custodial setup.

The concrete problem it solves is integration fragmentation. Without a shared standard, every website that wants Lightning payments or Lightning-based login has to build its own connection to a specific node implementation, and every user has to expose node credentials or copy invoices by hand. Alby replaces that per-site work with one WebLN provider that any site can call, and it packages the common flows — payment requests, invoice generation, message signing and verification, and dynamic invoice creation — behind that single interface.

Key capabilities

• Custom budgets and allowances that enable auto-payments and payment streams.
• Multiple accounts across Lightning node backends such as LND and CLN, plus custodial options.
• Full WebLN support: send and receive payments, generate invoices, signMessage, verifyMessage and dynamic makeInvoice.
• LNURL support covering LNURL-pay, LNURL-auth and LNURL-withdraw.
• Keysend payments, which send funds without requiring an invoice from the recipient.
• Payment history and metadata, so transactions are tracked together with the website metadata attached to them.
• Nightly development builds published as firefox.xpi.zip and chrome.zip for users who want the latest master build ahead of release.

Who uses it and how

• Individual users who want to pay and log in on Lightning-enabled sites without running node management tooling in the browser, since the extension focuses on web payments rather than advanced node management.
• Node operators and self-custody users who point one or more accounts at their own LND or CLN backend, while other users rely on a custodial backend for the same interface.
• Nostr, Liquid and onchain users who need a key signer in the browser rather than a separate application.
• Website and application developers who integrate WebLN once and then reach every Alby user, rather than writing bespoke per-wallet Lightning code.
• Contributors: the project labels issues as good first issue and as design, maintains a Figma master design file, and accepts translation help through its contribution guide.

Getting started

Install from the official store listings — Add to Chrome, Opera, Brave and other Chromium browsers, or Add to Firefox — with nightly firefox.xpi.zip and chrome.zip builds available for development versions. Developers should refer to doc/SETUP.md for setup and to load the extension into a browser.

How it compares

No comparable products are named in the facts for this entry, so it stands alone in this registry under Productivity & Utilities / Browsers & Extensions. Its distinguishing position, as described, is the combination of a WebLN payment interface with key signing for Nostr, Liquid and onchain use, rather than a single-purpose wallet.

When to use it — and when not to

Choose it when the goal is a browser-level WebLN wallet and signer that can sit in front of an existing LND, CLN or custodial backend. Do not choose it if advanced node management is the requirement, since the extension deliberately targets web payments instead, or if a browser outside the Chromium family and Firefox is needed, because further browser support is listed as coming rather than shipped. Note also that nightly builds carry the warning that updating may require reconfiguring the wallet, and the repository currently shows 237 open issues against 584 stars and 226 forks, so users who need stability should stay on official releases.