When it comes to modern UI design and web design, a good quality icon set is invaluable and can make or break a design.
There is certainly no shortage of icon sets and there are many different styles of icons floating around the internet today. Just a quick Google search will reveal hundreds of icon sets, many of which are 100% free and open source.
The problem is not all icon sets are created equal. When we were building Untitled UI v1.0 we looked at dozens and dozens of open source, free, and paid icon sets. We even explored custom icon packs. Some were good, but we found the vast majority of icon sets lacked in quality, were inconsistent, or simply too small — usually a combination of all three. Surprisingly, we found that many of the best icon sets were 100% free!
Choosing a good quality icon set can be just as time-consuming as creating your own custom icons. We’ve done an extensive search for the highest-quality free icon sets for UI design and compiled them here for you in one place.
This isn't an exhaustive list with 50 free icon sets for you to pull apart. We've intentionally kept this list as short as possible and have only included the absolute highest-quality free icon sets so you don't have to waste your time.
What is an icon?
In UI design and web design, icons are small graphical representations of a functionality or concept. They provide users with quick and recognizable visual cues that are easy to understand.
For example, lock icons indicate something is locked. Tick icons indicate that an action has been completed or saved. Trash icons mean delete or remove. Icons are so ubiquitous in modern UI and apps that we don’t often don’t even have to think.
Consider these icons below. You should immediately recognize what they represent:
- House icons for the home page
- Three horizontal line icons to indicate a hamburger menu
- Magnifying glass icons for search
- Pencil icons to edit or modify content
- Heart or thumbs-up icons to like something
- Heart or star icons to favorite something
- Bookmark icons to save a bookmark
- Arrow coming out of the top of a square icons to share something
- Arrow pointing down into a square or cloud icons to download something
- Gear or cog icons for settings
- Lock icons to show something is secure
- Arrow pointing into a cloud or out of a box icons to upload something
- “X” icons to close or exit out of something
- Funnel icons to sort or filter content
- Link icons to add a link to something
- Arrow pointing out of a box icons to log out of something
These are what we like to call universal icons or default icons. They’re everywhere, and it’s pretty clear to the user what they mean. Boring? Maybe. But they work.
When it comes to choosing an icon pack or designing custom icons, don’t try and reinvent the wheel. These universal and default icons are familiar to users already and changing them up so they’re unrecognizable just introduces a new challenge unnecessarily.
This doesn’t mean you can’t make your icons a little more visually interesting. As long as you don’t stray too far from the universally recognized symbol, it’s usually 100% fine. Here are the same examples using Untitled UI Icons in a duotone style:
Icons are important for UX
Icons are a crucial part of web design and UI design but are often overlooked. They’re especially important in information-dense UI design, such as dashboards or complex SaaS products.
High-quality icons can add style and visual interest to your designs. More importantly, when used correctly, good icon design can speed up user interactions by making actions immediately recognizable.
When you use a website or UI on any device, your eyes scan the content for the action(s) that you want to take. Some good examples of this are the home screen of your favorite app or a list of options in a menu. You’re not going to read every single word on the page, but you want to find what you’re looking for quickly.
This is where icons come in. Good icon design provides small visual cues for the user, helping you find what you’re looking for quickly and efficiently. As part of a consistent icon set, users quickly learn to associate certain icons with certain actions over time.
Sidebar navigation menus in UI design are the perfect example of this. Often, these are packed full of menu items and can be overwhelming for the user. Icons provide designs with quick and easy visual cues and make the menu list easier to scan.
While they don’t seem like much, icons in UI design make the process of navigating this menu and finding what the user needs significantly easier, reducing the cognitive load and making this navigation easier to remember over time.
At the end of the day, icons should be easy to understand
Icons are everywhere in the physical world as well. Road signs are a great example of clear and functional iconography. They're basically big icon sets. While they differ in style slightly around the world, they’re easy to understand and universally recognizable, even at a glance.
Imagine how chaotic and stressful driving would be if road signs and their icons were inconsistent and hard to understand and interpret? Or if new icons were being introduced all the time? Drivers should be able to drive past signage without needing to slow down or divert their attention to understand what they mean. In the words of Steve Krug, “don’t make me think”.
The same goes for icons in UI design and websites. While the consequences aren’t life-threatening like road signs, poor iconography and low-quality icon packs create a frustrating experience for the user by slowing them down and making them think.
The main objective of icons in your design are not only to look beautiful but to be easy to understand. There’s no reason they can’t be both, but icon design should be functional first and foremost.
Sure, weird and wonderful icons and custom icon packs might look more interesting, but if users don’t understand what they mean in a quarter of a second, your ego is impacting the overall user experience and they’ll get frustrated.
No matter what free icon set, icon font, or premium icons you choose, remember that icons should be functional first and visually interesting second. Too many designers fall into this trap and choose interesting icon sets at the sake of usability.
Stick to icons and icon sets that people recognize wherever possible, especially for common user interaction or tasks like the examples above.
How to choose an icon set for your project
When starting a new web design project, choosing high-quality icons from the start will save you a lot of headaches and wasted time down the track. It can be a tough decision, especially because there are simply so many out there, with new icons popping up every month.
Thankfully, there are a few key things you can look out for. A good free icon set should check these boxes:
The icon set should be large enough to suit your project
Look for icon sets with a wide range of icons that will cover your needs. You won't need 10,000+ icons but aim for at least 250+ essential icons that you'll almost certainly need.
Otherwise, you’ll find yourself painstakingly creating custom icons down the track. This can be incredibly time-consuming, but also leads to inconsistencies.
The icon set should be consistent and professionally crafted
Good quality icon sets are consistent, optically balanced relative to each other, and just “look good”. They should be clear enough to work in dark themes and across all devices.
It can be hard to spot if you’re new to design, but inconsistent and unbalanced icons are very easy to spot.
Look for icon sets that include SVG format or Figma files so you can export them to SVG or PNG formats. If you're more familiar with Adobe software, look for AI or EPS formats. Avoid free icon sets that only come with PNG formats.
The icon set should suit your brand
This can be subjective, but icon sets can vary drastically in style and how they “feel”. Often, premium or paid icon packs are a distinctive style to differentiate them from other icon sets.
Many icon sets come with several different styles. In general, rounded icons tend to feel more fun and playful, while tight and minimal icon sets can feel more modern.
Choosing an icon set that is consistent with your brand will ensure they don’t look out of place. If in doubt, opt for a neutral and clean icon set that will work well with anything.
You probably don't need premium icons or a custom icon set
Don't fall into the trap of spending money on premium icons upfront — often, some of the best icon packs for your project are 100% free to use and most premium icon sets come with a free version to try first.
Many paid and premium icon sets come with "free" versions, but these usually lack key essential icons so you end up purchasing the icon set later on. While this is fine, just make sure you're aware of this before you commit!
The same goes for typefaces — there are many high-quality free fonts that suit almost any project in modern UI design. We explored this idea in our post on the best free fonts for modern UI design.
It's better to pick an icon set from the start — don’t wing it
Choosing a good icon set from the start means you won’t be picking and choosing icons from different icon sets as you go. This can be an absolute nightmare because as your icon set grows, it will become more and more inconsistent and messy, even to the untrained eye.
Nothing stands out more in modern UI design than inconsistent icons.
This is especially important for large design projects. As you scale, inconsistent or poor-quality icon sets will only build design debt. Eventually, you (or another designer) will have to go back and tidy these up or replace the icon set with professional icons that work well together. This can take months and is wasted time and money.
These are examples of the mail icon from different icon sets around the internet. As you can see, they all have a very different style.
Most of these icons look okay on their own, but next to different styles they look out of place. Some look a little dated, but it can be hard to tell why and without context... Usually, it’s a combination of many micro-decisions that were made by the icon's designer — style, stroke weight, size, aspect ratios, fill — all of which factor into the overall look and feel of the individual icons and the icon set as a whole.
High-quality icons are effective, but also look good
Quality and consistent icons can make a website design or app more visually attractive. There's no reason why icons can't be functional and also aesthetically pleasing.
While these mail icons in the example above would work just fine as part of a consistent icon set, mixing and matching different styles made by different icon designers for different purposes will always look inconsistent and unprofessional.
At best, this makes your designs look bad. At worst, this lack of care and professional polish can lead to mistrust of your product by your users. A consistent and free minimal icon pack with 250 icons will always be a better choice than an inconsistent icon pack with 10,000+ icons.
You don’t realize the power of a high-quality icon set until you start using one. A good free icon set saves you time and money usually spent on meticulously creating icons one-by-one, or even worse, constantly fixing existing icons so they're more consistent and optically balanced.
You can avoid most of these issues and pitfalls by choosing a high-quality icon set from the start. This will save you time, headaches, and expensive design+tech debt down the track.
The great news is that many of them are 100% free! Here are our top picks for the best free icon sets for modern UI design: