What Heroicons does
Heroicons is a set of SVG icons made by the team behind Tailwind CSS. It is released under the MIT license and includes React and Vue libraries. Icons come in Outline, Solid, Mini, and Micro styles, and the Outline style uses a 24x24 grid with a 1.5px stroke. Documentation is hosted on GitHub, and a Figma file is available. The page implies use by developers working with React or Vue and by designers working in Figma. The page does not state a pricing model.
How Heroicons compares with its closest alternatives
All 5 closest alternatives have a free plan, as Heroicons does. Only Flaticon lists a starting price, $10 a month. 2 of the 5 offer an API; FalcoScan's records show none for Heroicons. Heroicons offers a web app. Of the alternatives, all 5 offer a web app. Heroicons was founded in 2020; the alternatives were founded between 2012 and 2021, 3 of them earlier.