Icons are the silent, universal language of digital products. They guide users, signify meaning, and—most importantly—communicate your brand's personality in a fraction of a second. But not all icons are created equal. Choosing the correct style is crucial for a cohesive, intuitive, and effective User Interface.

Let's dive into the 7 essential icon types you need to know and understand where and why to use each one.

The 7 Icon Types and Their Ideal Use Cases

1. Linear

  • What they are: Simple outline-style icons with no fills.
  • Use Case: Commonly used in minimalist and modern interfaces for clarity and scalability. Their simplicity is ideal for navigation and secondary actions where visual noise needs to be kept low.

2. Bold

  • What they are: Solid, filled icons with strong visual weight.
  • Use Case: Often used to draw immediate attention to primary actions or key/active navigation elements. Think of a filled-in "Home" icon indicating the user's current location in an app.

3. Duocolor

  • What they are: Icons that utilize two contrasting colors to add depth and emphasis.
  • Use Case: Frequently used in dashboards or data visualization interfaces. The two-tone approach helps distinguish different states or layers of information without sacrificing clarity.

4. Bulk

  • What they are: Heavily filled icons with soft edges and playful proportions.
  • Use Case: Typically used in friendly, approachable UI designs or illustrations. They communicate a lighthearted and modern aesthetic, great for younger or consumer-facing apps.

5. Broken

  • What they are: Outlined icons with intentional gaps in their strokes.
  • Use Case: They offer a unique, creative look often used in modern or experimental design systems. They are best for applications aiming for a highly distinct visual style.

6. 3D

  • What they are: Realistic or stylized three-dimensional icons with lighting and depth.
  • Use Case: Used to create a premium, engaging, or tactile user experience. They work well for showcasing premium features, app store previews, or high-end product visuals.

7. Illustrated

  • What they are: Detailed, hand-drawn-style icons that add personality and storytelling.
  • Use Case: Usually found in onboarding screens or marketing visuals. They are perfect for establishing a strong brand voice and creating emotional connection with the user.