Icons are a requirement for any web-related project but creating your own custom icons for each project is rarely practical as it’s so time-consuming. On the other hand, finding those hidden treasures in a pool of tens of thousands of icon packs also takes time. And finding great icons that are also free is even more difficult.
So, here are 25 noteworthy icon sets that would make a great addition to your arsenal and help to grab the user’s attention. There is a wide variety of icons here: you’ll definitely find at least a few sets that you can put to good use in your own projects, whether personal or commercial.

01. Iconmelon

This brilliant collection of various flat icon sets has a minimal website for some great minimal icons.

02. Social icons

Featuring 150 monochrome social icons designed with simplicity in mind, this set consists of a variety of fully scalable icons provided in AI, EPS, PNG and SVG formats. They are completely free to use in both personal and commercial projects.

03. Free Furry Cushions Social Icons Set

Got a furry site? Then these furry social media icons will be perfect for your site. Download the six icons for free and use them in your projects without any restrictions.

04. Social media icons pack

Who doesn’t need to use social media icons on their site or blog? Check this set out. It consists of 74 social media icons that would that would be perfect for almost any type of design, whether you’d like to use them offline or online.

05. Color stroked icon set

This social media icon set includes 22 free hand icons that you can use for both personal and commercial purposes. It comes with icons for Delicious, Flickr, Twitter, Digg, Delicious and more. Check it out!

06. Supernova icons

A charming icon set for Android and iPhone that includes 19 diverse icons of 84x84px size.

07. 80 mini icons

Featuring 80 pixel perfect mini icons available in both PSD and Icon Font format. These clean and elegant icons are perfect for any project.

08. Simple and practical web icon vector graphic

A variety of extremely useful icons that can be used for both personal and commercial projects.

09. 99+ free vector icons

Building your own site from scratch? If you want to keep it nice and simple, check out this great collection of 99 icons that are beautifully hand crafted for mobile, web and print projects. Keep in mind they’re only free to use in personal projects.

10. Free flat icons

Fantastic set of flat designed icons that feature icons for calendars, emails, clocks, maps and more.

11. Mono icons

A beautiful, minimal set which includes 108 unique icon designs that are available as a PNG at 32x32px that you can customise as you see fit.

12. Metrize icons

Here’s fantastic resource for designers and developers – a free collection of 300 metro-style icons that you could use for your apps or web projects. They’re all free to use in both personal and commercial projects and the download includes not only the PSD, SVG, ESP and AI but also the web font.

13. Tab Bar Icons iOS 7

Elegant iOS 7 inspired tab bar icon set that you can use in your apps. You can download and customise them in PSD, AI and ESP formats.

14. Chunky Pika Icon Set

Check out this Pika-style vector icons released by the Dutch designers at Dutch Icon. The set includes 42 chunky pixel-perfect icons that you can use for your next personal or client project.

15. Iconic

Here’s a great set of simple yet attractive icons that would be perfect for a minimal design. Iconic is an open source icon set that can be downloaded in PNG, SVG, SWC as well as other formats, thus allowing you to customise them to fit and match your design.

16. 44 Shades of Free Icons

Need some simple icons for your next client project? Here’s a set of 44 icons you can use. They’re in a PSD format, enabling you to easily edit and adapt them.

17. Token icon set

Token includes 128 unique icon designs, available as an ICO bundling of 16x16px, 32x32px and 256x256px icons, or as a PNG at 128x128px. Each icon has both dark and light variants, and comes along with a PSD which includes the layer styles for each resolution.

18. Flat icons (PSD)

Colourful flat icon set that you can download in a PSD format, allowing you to change colours and adapt each icon so it integrates perfectly into your new project. Check them out.

19. Free 32px icons set

Here’s a complete icons set that includes just about every icon you require on your new site. Starting from Skype, Facebook and Twitter icons to RSS, coffee, like/unlike and many more.

20. Flat icons: More than 3600 icons

A fantastic softly coloured yet vibrant flat-styled icon set comprised of more than 3600 flat icons. It includes icons for social networking sites, payment and credit card, all in PNG format. The set is only free to use for personal projects.

21. 48 flat designer icons

If you’re a fan of minimalism then this icon set might be perfect for you. It consists of 48 free icons for office, social and travel, all supplied in AI and PNG formats, fully scalable and in full colour and monochrome coral.

22. Plex icons set

This set includes over 100 icons for calendars, antivirus, clocks, email, Microsoft Office applications, social media networks and more. Check it out!

23. Vectory mini free

Vectory is a huge collection of more than 1000 icons created by Icojam, all in PNG format. Great for when you’re designing a new site as you can use them freely for both personal and commercial projects.

24. Eldorado mini free

Yet another large collection of mini icons from Icojam with over 1200 40×40 pixel icons that you can use on your site or on client sites. Free to use for both personal and commercial projects.

25. 2600 Flag Icon Set

This epic set contains 2,600 flags in several sizes along with 2 variants – flat and glossy.