Phosphor Icons

Phosphor is a flexible, 9,161-icon family designed by Helena Zhang and Tobias Fried. Every concept ships in six weights — thin, light, regular, bold, fill, and duotone — so you can dial the optical weight to match body type, headings, or branding without sourcing from a different library. Phosphor's letterforms are unusually warm for a technical icon set: curves are generous, stems are even, and the bold weight reads almost typographic. It's a popular pick for design systems where icons need to scale from 12-pixel inline glyphs to 64-pixel hero illustrations without redrawing. The MIT license, well-documented React, Vue, Web Components, and plain-SVG ports, and the deliberate range of weights make Phosphor one of the better defaults when you want one library to cover every visual surface.