Top 10 Icons User Interface Libraries in 2025

In UI design, icons play a key role in guiding users and improving interaction. Yet, integrating icons in user interface effectively can be challenging. This article simplifies the decision-making and design process further, spotlighting top icon sets and sharing essential tips for enriching your UI.

Get ready for direct, practical guidance on choosing and using awesome icons, that resonate with your users and complement your design.

In this blog, we're gonna cover free icon library, open source icon library, as well as some premium icon libraries, so you could choose the optimal open source icon library for your UI.

Introduction to Icon Libraries

Icon libraries are essential tools for designers and developers, providing a vast collection of pre-designed symbols that enhance user interfaces. Instead of creating icons from scratch, these libraries offer a huge library of ready-to-use assets in formats like SVG, web fonts, and React components, making integration seamless.

Whether it's a minimalist, free icon set for clean designs or a comprehensive pack for enterprise web and mobile applications, choosing the right icon library improves UI consistency, accessibility, and overall user experience.

With options ranging from open-source collections to premium offerings, developers can easily find a library that fits their project’s needs. Icons can be used in various formats such as SVG, PNG, and React components from Open Source icon libraries.

Types of Icon Libraries

Icon libraries come in various forms, each catering to different needs and preferences. The three main types are open-source icon libraries, premium icon libraries, and free icon libraries.

Open-source icon libraries are freely available for use and modification, often created by a community of designers and developers who share their work for the greater good. These libraries are ideal for both personal and commercial projects, offering flexibility and a collaborative spirit. Additionally, they encourage community support and contributions, enriching the icon collections over time.

Premium icon libraries, on the other hand, provide high-quality, meticulously crafted icons that are perfect for commercial projects where a polished, professional look is paramount. Many premium icon libraries offer a consistent design language that aids in creating visually cohesive interfaces.

Lastly, free icon libraries offer a selection of icons at no cost, making them a great choice for personal projects or for those on a tight budget. Each type of free icon library has its own set of advantages, allowing you to choose the one that best fits your project’s needs.

Top 10 Icon Libraries

Here are the top 10 icon libraries, each with its unique features and benefits:

1. Hugeicons

Website: https://hugeicons.com/

Specifications:

• 4000+ free icons
• Over 40,000 icons across 57 categories
• Multiple styles such as stroke, two-tone, duotone, solid, bulk, with options for rounded or sharp corners
• Figma Plugin
• Figma variant and component file
• Icons are available in SVG and PNG formats amongst othe formats

Pros:

• Extensive library catering to a wide range of design needs
• Multiple styles, suitable for diverse visual needs

Cons:

• No cons noted

Hugeicons provides a rich collection of icons, featuring an extensive library with easily recognizable versatile styles such as stroke and solid. This caters to the refined visual demands of high-end creative projects and a diverse range of design needs, with over 40,000 icons spread across 57 categories.

Hence, it's an ideal resource for designers seeking a broad icon set to match various diverse categories of design aesthetic appeal. Best for web apps and mobile apps.

Hugeicons offers a one-time payment license, making it a cost-effective solution for long-term use of premium icons. This means that while the initial investment may seem steep, the extensive range and quality of the icons provided can prove to be a worthwhile expenditure for businesses and designers who anticipate the need for a comprehensive icon library over time.

Additionally, the one-time payment model eliminates the worry of recurring fees, allowing for better budgeting and financial planning in project development.

2. Phosphor Icons

Website: https://phosphoricons.com/

Specifications:

• Over 9000 icons available in 6 distinct weights: Thin, Light, Regular, Bold, Fill, and Duotone
• 16 x 16 pixels baseline size for enhanced readability
• Utilizes icon font technology for seamless integration

Pros:

• Versatile design suitable for a multitude of applications
• Consistent size for enhanced readability on small screens
• Free icons
• Open source icon library

Cons:

• No cons noted

Phosphor Icons feature a generous collection of over 9000 icons in 6 distinct weights. Their variety makes them a flexible option for diverse design aesthetics. While designing icons, these consistent icons are crafted with a 16 x 16 pixels baseline size for enhanced readability on small screens and can be scaled up effectively for larger displays, making the most of the available screen real estate.

These universally recognizable icons ensure a seamless user experience across desktop applications on various platforms. Icons created using SVG technology are resolution-independent and scalable, making them suitable for different screen sizes and resolutions.

• Thin
• Light
• Regular
• Bold
• Fill
• Duotone

Their variety makes them a flexible option for diverse design aesthetics. While designing icons, these consistent icons are crafted with a 16 x 16 pixels baseline size for enhanced readability on small screens and can be scaled up effectively for larger displays, making the most of the available screen real estate. These universally recognizable icons ensure a seamless user experience across desktop applications on various platforms.

What sets Phosphor Icons apart is their:

• Streamlined and versatile design, making them suitable for a multitude of applications, including interfaces, diagrams, and presentations
• Maintenance of raw stroke information, allowing designers to adjust the style according to their specific project needs
• Adaptability to different design requirements while preserving consistency across applications

3. Feather Icons

Website: https://feathericons.com/

Specifications:

• Open source icon collection
• Suitable for minimalist design
• Available under a creative commons license.

Pros:

• Clean and simple designs suitable for contemporary projects
• Clarity and ease of use
• Open source icon library

Cons:

• Limited detail may not be suitable for all types of projects, including commercial projects

Feather Icons, an open-source collection icon fonts, is recognized for its simplicity and elegance. It is web font that's well-suited to minimalist interface designs, ensuring clarity and ease of use that align with contemporary project requirements. Feather Icons prioritize lightweight design and allow for easy customization by adjusting the size, stroke width, and color.

However, the limited detail in Feather Icons' design may not be suitable for all types of design projects however, particularly those requiring more intricate visuals. Nevertheless, they have been praised for their clean and simple designs, making them a go-to choice for web designers also aiming for a minimalist aesthetic.

4. Iconoir

Website: https://iconoir.com/

Specifications:

• Unique, stylish icons that distinguish it from traditional icon sets
• Top-quality, open-source icon library
• A compelling cost-free alternative to other icon resources.

Pros:

• Distinctive design ideal for projects requiring creative flair
• High-quality, open-source icon library

Cons:

• May require extra design effort to integrate into certain projects

However, while web developers and projects that benefit from a touch of creative flair find Iconoir to be a fresh option, it might demand extra design effort. Despite this, Iconoir's distinctive design adds a level of elegance and uniqueness to interfaces, and web applications, making it a perfect choice for projects requiring a touch of artistry and creativity.

5. Untitled UI Icons

Specifications:

• Specifically designed for the Untitled UI kit

Pros:

• Cohesive design enhances interface aesthetics
• Perfectly matches the modern and sophisticated look of the Untitled UI kit

Cons:

• No cons noted

Untitled UI Icons, meticulously crafted, are designed to blend flawlessly with the Untitled UI kit. They contribute to the overall design harmony of projects by mirroring the modern, sophisticated aesthetic of the Untitled UI kit.

However, their specificity to the Untitled UI ecosystem might restrict designer flexibility when attempting to diversify project aesthetics. Despite this, for those already using the Untitled UI kit, these new icons should provide a cohesive and modern look to any interface design.

6. Majesticons

Website: https://www.majesticons.com/

Specifications:

• Vibrant and audacious set of icons designed to stand out

Pros:

• Bold lines and distinctive style command user attention
• Suitable for interfaces where a strong visual impact is desired

Cons:

• Dominant nature of icons can potentially overwhelm an interface

Majesticons features a lively and daring set of place icons designed to stand out and captivate user attention within the user interface. Their bold lines and distinctive style make these popular icons particularly effective for interfaces requiring a potent visual impact.

However, the dominant nature of Majesticons can be a double-edged sword, potentially overwhelming an interface if used too liberally. Despite this, for projects that aim to make a statement or need to highlight certain aspects prominently, Majesticons are an excellent icon set to consider while being mindful of their powerful visual presence.

7. Unicons

Website: https://iconscout.com/unicons/free-line-icons

Specifications:

• Comprehensive collection of over 7000+ free vector icons
• Variety of icon styles such as line, monochrome, solid, and thin line

Pros:

• Extensive collection of icons
• Multiple styles offer flexibility in design

Cons:

• Some niche categories may lack options

Unicons offers a broad collection of over 7000+ free vector icons as a Figma plugin. Their variety of free icon pack styles includes:

• Line
• Monochrome
• Solid
• Thin line

This variety can help maintain brand uniformity across different platforms. While the icons organized in Unicons is comprehensive, some niche categories may lack options, requiring supplementation with additional icons to fully meet branding needs. Nevertheless, with its extensive collection material icons and variety of styles, Unicons offer flexibility and a wide range of design options to designers.

8. Heroicons v1.0

Website: https://v1.heroicons.com/

Specifications:

• Over 230 free icons in two distinct styles

Pros:

• Wide array of categories suitable for use in modern user interfaces
• Official libraries for React and Vue

Cons:

• No cons noted

Heroicons v1.0 boasts a wide variety of universal icons suitable for modern user interfaces. With over 230 free icons in two unique styles, it provides an expansive and wide range of design possibilities. Heroicons v1.0 features official libraries for React and Vue, facilitating the use of icons as dedicated components within these frameworks.

Despite being a deprecated version, it still offers a wide range of icons suitable for modern interfaces, making it a valuable resource for designers.

9. Heroicons 2.0

Website: https://heroicons.com/

Specifications:

• Updated version with refined designs and structure
• Some icons have been deprecated and renamed for clarity

Pros:

• Refined designs and updated structure
• Icons offer modern aesthetic for interfaces

Cons:

• Transitioning from the previous version may require some effort

Heroicons 2.0, an upgraded version of Heroicons, offers new icons with enhanced designs and structure tailored to the requirements of modern interface designs. It features some deprecated icons, like certain arrow icons which have been renamed for better clarity, indicating a progression in the free icon set's structure and naming conventions.

Transitioning to Heroicons 2.0 from the previous version involves:

• Adapting to the refined designs and updated structure
• Putting in some effort to make the transition
• Enjoying a heightened modern aesthetic for interfaces

Despite the transition, Heroicons 2.0 continues to be a reliable and valuable resource for designers seeking to update and refine their interface designs.

10. Iconizer

Website: https://iconizer.net/

Specifications:

• Customizable icon search tool with options to modify colors, size, and brightness

Pros:

• Allows users to modify icons according to their needs
• Enhances designers' skills in component utilization

Cons:

• No current integrations with other tools or platforms

Iconizer transcends being just an icon set and serves as a customizable icon search tool, enabling modifications in colors, size, and brightness to meet your unique needs. This customization capability adds an appreciated level of flexibility and control for designers.

However, it's worth noting that while Iconizer features a Figma plugin for direct browsing and easy integration of specific icons into designs, there are no current integrations with other tools or platforms listed on the website. Despite this, Iconizer remains a valuable tool for designers looking to enhance their skills in component utilization and create tailor-made icons for their projects.

Choosing the Right Icon Library

Selecting the right icon library can be a daunting task given the plethora of options available. Here are some essential tips to help you make an informed decision:

• Consider the Style and Format of the Icons: Ensure the icon library offers icons in the style and format that align with your design needs. Whether you need minimalist, detailed, or flat icons, the right library should cater to your specific aesthetic requirements.
• Check the Quality of the Icons: High-quality icons are crucial for a professional look. Look for libraries that offer well-designed, visually appealing icons that enhance your project’s overall appearance.
• Consider the Customization Options: Flexibility is key. Opt for an icon library that allows you to customize the icons, such as changing their size, color, and other attributes to fit seamlessly into your design.
• Check the Licensing Terms: Licensing can impact how you use the icons. Make sure the library’s licensing terms are compatible with your project’s needs, especially if it’s a commercial endeavor.
• Consider the Cost: Budget is always a consideration. Whether you opt for a free or premium icon library, ensure it fits within your financial constraints while still meeting your quality and functionality requirements.

By keeping these factors in mind, you can choose an icon library that not only enhances the visual appeal of your project but also aligns with your functional and budgetary needs.

Decoding Icon Set Parameters

In icon design, certain key parameters are worth noting:

• Uniform line widths and a consistent design style within an icon pack are integral to crafting a unified set.
• Uniformly applying effects like shadows or gradients across all icons facilitates consistency.
• Offering multiple icon sizes provides versatility for different design requirements.
• Ensuring icons have a consistent visual size across a set contributes to a balanced appearance when viewed together.

Moreover, high quality icon libraries and sets that are available in a variety of formats and support popular design tools and frameworks enable designers to use them across different applications, ensuring broad compatibility and seamless integration. By understanding these parameters, designers can create cohesive and versatile open source icon libraries and sets that enhance the overall user experience.

Aligning Icons with Your Project Goals

Choosing appropriate icons for a design project can enhance user interaction speed and infuse style and visual interest into the user interface. Thoughtfully selected icons can:

• Reinforce a strong brand identity by augmenting interface cohesion and visual appeal
• Improve usability and user experience
• Provide clear and intuitive navigation
• Communicate information quickly and effectively

However, it's crucial to use icons deliberately as excessive or meaningless icons can reduce usability and clutter the design. For users with disabilities, icons can make interfaces more accessible by providing an alternative to text.

Icons should be easy for users to find, recognize, and comprehend within the context of the interface, and it is important to test for any cultural differences and accessibility concerns. By aligning icons with your project goals, you can create an intuitive and engaging user interface with the right interface elements.

Testing Icons for Optimal User Experience

Usability testing is crucial for verifying the effectiveness of icons in a user interface. Examining icons in their real-world context assists in assessing their findability and recognizability within the overall design. Icons contribute to the scanability of interfaces, allowing users to rapidly locate and comprehend features or actions.

Usability testing of icons can reveal instances where users confuse one icon for another, necessitating a redesign for clearer understanding. The clarity of an icon's function can be validated by testing whether users can successfully interpret its purpose. By conducting thorough usability testing, designers can create icons that not only look good but also enhance user interaction and engagement.

In conclusion, well-designed icons are indispensable in enhancing user experience and setting the tone for user interaction. Whether you're looking for a set of minimalist icons like Feather Icons or a more audacious set like Majesticons, the key is to choose an icon set that aligns with your project goals and enhances the overall user interface.

Remember, icons are not just decorative elements but also serve as visual cues to guide users through the labyrinth of digital interfaces. So, choose wisely and make every last pixel perfect icons count.

How to Integrate Icon Libraries in Your Design Workflow

Integrating icon libraries efficiently into your workflow can significantly enhance productivity. Below are the best methods to incorporate icons into different design and development environments.

1. Importing Icons into Design Tools

• Figma: Many icon libraries, such as Hugeicons and Phosphor Icons, have dedicated Figma plugins, allowing designers to quickly search and insert icons directly into their projects.
• Adobe XD & Sketch: While these tools do not have as many built-in integrations, designers can still import SVG files manually and organize them into asset libraries for easy reuse.

2. Using Icons in Development

• React & Vue: Libraries such as Heroicons 2.0 and Phosphor Icons offer native React and Vue components, enabling developers to use icons as reusable UI elements.
• Webflow: Designers can upload SVG icons or use a CDN-based icon font to integrate icons into their Webflow projects.
• CSS Sprites: For websites with high performance demands, CSS sprite sheets help minimize HTTP requests by bundling multiple icons into a single file.

3. Best Practices for Icon Management

• Centralized Icon Library: Keep all icons organized in a design system to maintain consistency across projects.
• Consistent Naming Conventions: Use descriptive names such as icon-user-outline to make searching easier.
• Version Control: Store icons in a repository like Figma's shared library or Git for tracking updates and changes.

By streamlining the integration process, designers and developers can enhance their efficiency and maintain a cohesive UI experience across platforms.

Icon Customization Techniques

Customizing icons to align with a brand's visual identity is essential for maintaining design consistency. While many icon libraries offer ready-to-use icons, adjusting their appearance can help designers create a unique user experience that aligns with a brand’s identity.

1. Changing Colors and Stroke Width

One of the simplest ways to customize icons is by modifying their color and stroke width. Most vector-based icon sets come in SVG format, allowing easy adjustments using design tools such as Figma, Adobe Illustrator, and Sketch. For example:

• Figma: Designers can change stroke width directly within the properties panel.
• Adobe Illustrator: Allows for advanced stroke adjustments, including variable stroke widths for dynamic effects.
• CSS Styling: In web development, icons in SVG format can be customized using CSS (fill, stroke, and opacity).

2. Combining Multiple Icons for Unique Compositions

For a more distinct look, designers can merge different icons to create new symbols. This is particularly useful when working with icon sets that offer modular components. Tools like Figma’s Boolean operations (Unite, Subtract, Intersect) make it easy to merge icons.

3. Using Figma Plugins for Easy Customization

Plugins such as Hugeicons provide real-time access to vast icon libraries, allowing designers to tweak icons directly within Figma. Other useful tools include:

• SVG Editor: Modify SVG properties within a design tool without breaking the file structure.
• Nucleo App: A desktop-based icon manager that allows real-time editing and exporting in multiple formats.

4. Adding Shadows and Effects for Depth

For more visually dynamic interfaces, designers can add subtle shadows or depth effects to icons. While flat icons work well for minimalist designs, slight layering effects can enhance UI aesthetics, making buttons and elements more interactive.

By using these customization techniques, designers can maintain branding consistency, improve usability, and create visually distinct UIs without compromising functionality.

Summary

In conclusion, well-designed icons are indispensable in enhancing user experience and setting the tone for user interaction. Whether you’re looking for a set of minimalist icons like Feather Icons or a more audacious set like Majesticons, the key is to choose an icon set that aligns with your project goals and enhances the overall user interface. Remember, icons are not just decorative elements but also serve as visual cues to guide users through the labyrinth of digital interfaces. So, choose wisely and make every pixel count.

Frequently Asked Questions

What does icons mean in UX?

Icons in UX are small visual elements that represent functions, features, or content within a user interface, helping users understand and interact with the interface more easily.

Are icons a GUI?

Yes, icons are a key element of graphical user interfaces (GUIs), with specialized symbols representing functions and actions within the interface.

What are the key parameters to consider when designing icons?

When designing icons, it's important to consider uniform line widths, consistent design styles, and multiple icon sizes to always create visually appealing, cohesive and versatile icon sets. This will ensure a professional and polished appearance for your icons.

What is the importance of usability testing for icons?

Usability testing is important for icons as it helps ensure their findability and recognizability within the design, and can reveal instances of user confusion.

What’s the difference between SVG and icon fonts?

SVG (Scalable Vector Graphics) icons are resolution-independent, meaning they scale without losing quality, making them ideal for responsive web design. They are also more customizable using CSS (e.g., changing colors, stroke width). On the other hand, icon fonts are collections of icons stored in a single font file, which reduces HTTP requests but may not offer the same level of customization as SVGs.

How do I choose between a free and premium icon library?

Free icon libraries like Phosphor Icons and Feather Icons are excellent for basic projects and general use. However, if your project requires extensive customization, licensing for commercial use, and high-quality icons, premium options like Hugeicons**** is a worthwhile investment. Always check the licensing terms before using any icon set in a commercial product.

What are the best icon libraries for mobile apps?

For mobile apps, it's crucial to use icons that remain clear at smaller sizes. Hugeicons, Unicons, and Iconizer offer scalable and adaptable icons perfect for mobile interfaces. Choosing a lightweight icon set also helps improve app performance.