Preact

What is Preact?

Preact is a JavaScript library for building user interfaces. It mirrors the React API but ships in roughly 3 kilobytes instead of React's 40-plus. Same component model, same hooks, same JSX. A fraction of the weight on the wire.

The difference is not just size. Preact talks to the real DOM more directly and runs its own lean diffing algorithm, so it stays fast on low-end phones and slow connections. Most code written for React runs on Preact through the preact/compat layer, which aliases React imports to Preact under the hood. That makes it a drop-in swap for a lot of projects, though edge cases around synthetic events and certain libraries still need checking. A marketing site that loads in under a second on 3G is the kind of place Preact earns its keep.

You reach for React when you need its full ecosystem and the absolute widest library compatibility. You reach for Preact when bundle size and load performance are the constraint and you still want a familiar developer experience. Solid and Svelte change the mental model entirely. Preact keeps React's model and trims the cost.

Preact at Dallonses

We use Preact when a project lives or dies on load time. Widgets that embed in a third party page. Landing pages measured by Core Web Vitals. Anything where every kilobyte the user downloads costs money or attention.

The honest part is that Preact is not always the answer. Some React libraries lean on internals that compat does not cover, and we test that before committing. When it fits, the win is real. We bring the same React skills our web development work already runs on, ship a much smaller bundle, and the client gets a faster site without a rewrite. We figure out together whether the tradeoff is worth it on your stack.

Shaving load time off a React app? Let's see if Preact fits.

Talk to us about Preact