Open source
Bootstrap Icons
Free, open source icon library with over 2,000 SVG icons
Icon LibrariesFree Bootstrap SVG icon set
12 tools like Fontello, chosen by what they do. About Fontello
Free, open source icon library with over 2,000 SVG icons

Large consistent icon sets in SVG and PNG formats
Open source UI icon pack with 480 icons for common actions

Icon and stock photo library made by independent creators
Icon sets in several styles, with free and Pro packs
Simple open source icons drawn on a 24x24 grid

Open source neutral icon set for designers and developers