# solid-countup > A Solid component that animates a number from one value to another. A take on CountUp.js for > Solid, with locale-aware formatting through `Intl.NumberFormat` and no runtime dependencies. `solid-countup` renders a single `` and animates its text content from one number to another. It is a Solid port of CountUp.js, with reactive props and a `ref` handle for driving the animation. Install it with `pnpm add solid-countup`. `solid-js` is a peer dependency (`^1.6.0`). The component does not animate on mount: it holds `startVal` until you call `start()` through its ref, or set `autoAnimate` to start it when the element scrolls into view. ## Usage - [About](https://solid-countup.d6f4e5.me/about.html): a plain HTML explanation of what the library does, the props it takes, and how to use it. No JavaScript required. - [About (markdown)](https://solid-countup.d6f4e5.me/about.md): the same explanation as markdown. ## Project - [Live demo](https://solid-countup.d6f4e5.me/): every feature, running in the browser. - [npm](https://www.npmjs.com/package/solid-countup): the published package, with the full prop table. - [Source](https://gitlab.com/d6f4e5/solid-countup): repository, issues and the README.