Free Icon Pack by ThemeIsle
The Noun Project
Nucleo
Font Awesome
Freepik
Streamline icons
Icons8
Flaticon
Free Icon Design Guide
IconStore
omg-img
Mosaic
Endless Icons
IconBros
Budicon Classic 2.0 [icon suite]
Material Design Icons
Free Icon Design GuideThe Noun Project - Creating, Sharing and Celebrating the World's Visual Language
IconStore - Free icon packs by first-class designers
Nucleo - Commercial vector icons and accompanying apps to manage and customize them.
omg-img - Insert icons directly into your HTML just by coding
Font Awesome - Font Awesome makes it easy to add vector icons and social logos to your website. And version 5 is redesigned and built from the ground up!
Mosaic - Mosaic provides brands with solutions to store and categorize their digital graphic and photography files for quick and easy retrieval.