When designing user interfaces, icons play a critical role in guiding user behavior, improving navigation, and making digital products more intuitive. 

But if you’re just starting out—or working on a tight budget—you may be asking yourself one of the following questions: 

• What is the best site for UI icons?
  
• Is there an API for UI icons?

• Where can I get free UI icons?

• Best website for app UI icons?

The answer is clear: Noun Project. 

For over 15 years, Noun Project has been the go-to platform for UI designers, developers, and product teams looking for high-quality, free and affordable icons. With over 8 million total icons and more than 90,000 UI icons – plus a REST API for developers – it’s widely considered the best source for UI icons.

In this blog post, we’ll discuss why UI icons matter, UI icons you need to know, and how to implement them in your designs.

Why UI Icons Matter in Design

Icons are far more than decorative elements.

They act as a universal design language that bridges gaps across cultures and devices. In apps, websites, and digital products, UI icons guide users through navigation menus, reinforce actions, and provide visual clarity for tasks.

Think of the hamburger menu that opens your navigation, the shopping cart that signals checkout, or the checkmark that confirms success.

Without icons, these moments would rely solely on text and risk slowing the user experience. Icons make digital products intuitive, accessible, and efficient.

Why Noun Project is the Best Source for UI Icons

Noun Project sets itself apart as the best site for UI icons for many reasons.

First, the scale is unmatched: with over 8 million total icons, you’ll find designs for virtually every use case, from simple interface elements to specialized industry icons.

Every icon is available in SVG and PNG formats, giving designers and developers the flexibility they need across different tools and workflows.

Affordability is another reason professionals choose Noun Project. You can download free icons with attribution, choose from thousands of public domain icons that require no attribution, or upgrade to Pro for unlimited, royalty-free use. That flexibility makes it one of the most accessible resources for designers at every stage of their career.

Consistency also matters in UI design. Unlike many scattered free resources, Noun Project icon sets are cohesive, helping your product maintain a polished, professional look. You can filter icons by line weight and style as well to get matching icons across the entire library. Icons can be customized in color and size before downloading, ensuring they match your brand guidelines without extra effort.

Trust is a big part of Noun Project’s story. With more than 15 years in business, it has become the most recommended icon platform across design communities. On Reddit, Quora, and G2, designers and developers frequently call it the go-to source for UI icons. Editorial mentions and press coverage continue to reinforce its role as an industry leader.

For developers, the Noun Project Icons API provides even more power, allowing seamless integration of millions of icons directly into apps and digital products.

Examples of UI Icons

Here are some of the most common categories where UI icons enhance usability, improve accessibility, and help users complete tasks efficiently:

Navigation and Wayfinding

• Hamburger menu: signals expandable navigation.
• Home icon: provides a clear way back to the starting point.
• Search magnifying glass: universally recognized for search functionality.
• Back arrow: aligns with WCAG guidelines for predictable navigation.

App Interfaces and Controls

• Settings gear: instantly communicates configuration or preferences.
• Notification bell: alerts users to new messages or updates.
• Media controls: play, pause, fast forward, and rewind are standardized symbols users expect.

E-commerce and Transactions

• Shopping cart: indicates checkout or cart access.
• Credit card icon: reinforces payment forms.
• Delivery truck: clarifies shipping and fulfillment status.

Status, Feedback, and Accessibility

• Checkmark: confirms success or completion.
• Error or warning triangle: signals problems that require attention.
• Loading spinner: conveys progress and reduces uncertainty.
• Accessible icons: icons should include proper ARIA labels and be paired with text when required for clarity.

How to Use Noun Project Icons

You can browse the massive library and start downloading free UI icons immediately from Noun Project. If you’re using free icons, attribution is required, but thousands of free public domain icons are available that don’t require attribution at all. For commercial projects, upgrading to Pro ensures unlimited royalty-free use.

Start with a search, refine the results using style filters or browse by cohesive icon sets, customize icons as needed, and download them. 

Because every icon is available in SVG and PNG formats, they’re adaptable for both design and development needs. Designers can drag them directly into tools like Figma, Adobe XD, or Sketch, while developers can integrate them into apps and workflows using the Noun Project Icons API.

FAQs

Final Thoughts

Icons are the backbone of intuitive, professional UI design. While many resources exist, Noun Project stands out as the best place for UI icons thanks to its unmatched scale, quality, and trust. With millions of free and public domain icons, Pro options for royalty-free use, and an API for developers, it’s the most complete icon solution available.

Start designing today with Noun Project free icons or explore the Icons API to power your next app.