Icon Ninja collects 700080 free icons in 16306 icon sets, including 33350 vector icons and 666730 transparent background png icons, also you can generate icon css sprites online
Commercial, non-commercial, use them as you please. EOS icons comes with an MIT license, has an open source community, and welcomes your collaboration too.
kingsoft cloud vision
Download 4.7 Million+ high-quality free vector Icons, Illustrations, 3D Assets, and Lottie Animations that are available in static & animated formats at IconScout