1. Captain Icon
The Captain Icon Pack, which has over 350 hand-drawn vector icons, was created by designer Mario del Valle and is hosted on Github. Each of the icons has a unique design.
For websites and apps that require media, documentation, arrow, chart and so on, Dripicons, a set of 90 flat-style beautiful vector icon fonts, is great.
Many different types of fonts especially the best google web fonts, iOS or OS X apps are complemented by this icon font set. There is also a free Glyphicons set other than numerous paid sets. There are 610 basic fonts and 60 social fonts in this set. Under the Creative Commons Attribution 3.0 Unported license, the free Glyphicons fonts are released.
The latest version of Octicons, the in-house pack developed by GitHub, is 5.0 and has tons of icons with a few basic symbols. They are scattered across the GitHub website. You can use them on almost any interface as they are very user-friendly.
For personal and commercial use, the Sosa web icon font, which is a tailored font, is available for free. Over 160 icon fonts are offered by it.
For a whole range of sites, the Typicons icon set works well. In a somewhat similar style – simple outlines and smoothed corners, it has over 330 unique icons. On Github, this free pack is available. A web design agency can deploy them directly on any website. You can also make necessary alterations in them. You can even use them for iOS with just a few adjustments and adding bits of code.
You can add Zondicons very easily to your site and they are free. For downloading Zondicons, the main link is straight from the website.
8. Elegant Icon
There are over 360 icons in the Elegant icon web font, which is a free set. Among them, 50 are specifically for business. Any website design & development company loves to use them as the icon style is graceful and dazzling. Without diminishing the quality, these vector-based graphics can contract or expand.
The 400+ icons in the Entypo web icon set are excellent and top-notch among the free ones. You can access them easily. In two sets they are available, which are the social media pack and the main pack. Under the Creative Commons share-alike license, they are released.
10. MFG Labs
Their own web icon font set is released by MFG Labs, absolutely free and hosted on Github. You can easily access this set, which is fairly new. This is packed with the usual web font formats, created with Unicode PUAs in CSS.
With native app developers, the Ionic Framework is hugely popular, especially when it comes to the web to mobile apps. The Ionic Team created their own icon web font set, dubbing it Ionicons, inspired by this popularity and success. Hosted on Github, they are 100% free.
12. Font Awesome
As it is one of the original web fonts and has been around for ages, Font Awesome is a favoured choice of almost every web design agency. It is regularly updated with innovative icons and is acknowledged as the first key open source font icon. It has some great benefits and is freely downloadable on Github.
There are two free icon font sets in IcoMoon. With serif and sans serif fonts, they look amazing. The first set is made up of 490 rounded icon fonts in solid colors. Linearicons is the name of the second set. There are 170 fonts that are line based in it and under the Creative Commons Attributions Sharealike license, it is distributed.
There are over 1000 icon fonts that are retina ready in Fontello. They are very easily accessible, as they are available on Github. An archive with docs, fonts and CSS files is generated by Fontello.
There are more than 110,000 unique icons, offered in sets of 300, in Iconshock, one of the most famous and popular icon font sets.