Phosphor Icons
An icon family where every symbol ships in six weights: Thin, Light, Regular, Bold, Fill and Duotone. 1,248 icons and counting, MIT licensed, with official packages for React, Vue, Flutter, Swift, Elm, web components and plain web. A single prop takes a hairline interface to a heavy one, so you never swap library just to change how solid the UI feels.
Strengths
- Six weights per symbol (Thin, Light, Regular, Bold, Fill, Duotone): an active state renders without changing shape
- MIT licensed with official packages beyond React (Vue, Flutter, Swift, Elm, web components)
Best for
- An interface where state (active, selected, favourited) repeats everywhere and has to stay readable at a glance
- A design system that has to serve React and another platform from the same set of symbols