SpeedOf.Me has measured internet speed in the browser since December 2011, when it shipped as the first HTML5 speed test. It reports download, upload, latency and jitter and plots them live as the test runs, with no app, plugin or download, on desktops, phones, tablets, game consoles, smart TVs and cars.
The method is deliberate: one stream, from the browser, to neutral third-party CDN edge servers in more than 130 locations, over the same open-internet path your browsing and video already take. Tests that hit a server inside your own provider's network with many parallel streams report a best-case peak instead. That number is called Real-World Speed, and because the method has not changed since 2011 the figures stay comparable year over year.
Developers can run the same engine themselves. Drop in api.js, set an account key and domain, call SomApi.startTest(), and results return through callbacks, white-labelled, with nothing to host. Examples ship for vanilla JavaScript, React, Vue, Angular, React Native, Electron, Flutter, iOS, macOS, Android and Windows, and the portal reports calls, geography, device mix and speed trends.
AI agents get the same access through @speedofme/mcp, one npm package that is a Model Context Protocol server, a CLI and a Node SDK, working with Claude, Cursor, Windsurf, Zed, VS Code, Cline, Continue, JetBrains and Goose.
The Internet Speed Atlas aggregates millions of anonymised tests into real-world figures for 119 countries.