Bootstrap 4 doesn’t include an icon library by default, that’s why many developers looking for best icons. Where you can find awesome Bootstrap Icons for your project?
Please check following list, most icon sets include multiple file formats, but we prefer SVG implementations for their improved accessibility and vector support.
Open Iconic An open source icon set with 223 marks in SVG, webfont and raster formats
Octicons Octicons are a scalable set of icons handcrafted with <3 by GitHub.
Font Awesome Get vector icons and social logos on your website with Font Awesome, the web’s most popular icon set and toolkit.
OpenWeb Icons The OpenWeb Icons are a set of icons to show the support for the Open Web!
Simple Line Icons Simple line icons with CSS, SASS, LESS & Web-fonts files.
Typicons Typicons are free-to-use vector icons embedded in a webfont for easy use in any UI, whether it be on the web or in a native app.
Entypo+ Entypo is a set of 411 carefully crafted pictograms. The package contains an icon font — OpenType, TrueType and @font-face — EPS, PDF and PSD files. All released for free under the license CC BY-SA 3.0.