Huge collection of icons (over a million) created by the community that you can use whatever the nature of your project.
All the icons are royalty-free, with Creative Commons license, but a mention to the creator is recommended. If you turn into a NounPro user, attribution is not needed, while icons creator get a proportional part of your subscription.
When you find the icon you like, you can download it both in .png or .svg formats.
A macOS app is also provided, and I highly recommend using it, since your workflow will improve significantly. You just have to search the icon that match your needs, then you have the ability to drag and drop it in your favorite designing app (Sketch, Figma, Adobe CC, Keynote, Google Suite…) in your preferred format: .svg, .png or .pdf. (Limited icons for free users, the whole collection for NounPro ones. )