fui_kit — Flat UI icons for Flutter

fui_kit is a flat icon pack for Flutter with 2,988 SVG icons — 498 unique glyphs in 6 styles (regular, bold and solid weights, each with rounded or straight corners), based on the open source Flaticon UIcons set.

• 🎨 Themeable — icons follow your app's IconTheme (light/dark mode works out of the box).
• ♿ Accessible — first-class semanticLabel support for screen readers.
• 🔍 Searchable — browse every icon in the interactive gallery.
• 🧩 Drop-in — works anywhere a widget fits: IconButton, AppBar, ListTile, BottomNavigationBar…

Installation

flutter pub add fui_kit

Or add it to your pubspec.yaml manually:

dependencies:
  fui_kit: ^2.1.0

Quick start

import 'package:flutter/material.dart';
import 'package:fui_kit/fui_kit.dart';

class MyWidget extends StatelessWidget {
  const MyWidget({super.key});

  @override
  Widget build(BuildContext context) {
    return const FUI(RegularRounded.heart);
  }
}

Use it like any other icon widget:

IconButton(
  onPressed: () {},
  icon: const FUI(BoldRounded.settings),
)

ListTile(
  leading: const FUI(SolidRounded.user, semanticLabel: 'Profile'),
  title: const Text('Profile'),
)

The 6 styles

Every glyph exists in all six styles. Pick the class that matches the look you want:

Style	Class	Example
Regular Rounded	RegularRounded	FUI(RegularRounded.bookmark)
Regular Straight	RegularStraight	FUI(RegularStraight.bookmark)
Bold Rounded	BoldRounded	FUI(BoldRounded.bookmark)
Bold Straight	BoldStraight	FUI(BoldStraight.bookmark)
Solid Rounded	SolidRounded	FUI(SolidRounded.bookmark)
Solid Straight	SolidStraight	FUI(SolidStraight.bookmark)

Icon names are lowerCamelCase versions of the original kebab-case Flaticon names: address-book → RegularRounded.addressBook.

Customization

FUI(
  SolidRounded.heart,
  color: Colors.red,          // defaults to IconTheme color
  width: 40,                  // defaults to IconTheme size (24)
  height: 40,
  semanticLabel: 'Favorite',  // announced by screen readers
)

Parameter	Type	Default	Description
file (positional)	String	required	Icon constant, e.g. RegularRounded.add
color	Color?	IconTheme color	Tint applied to the icon
width / height	double?	IconTheme size (24)	Rendered size
semanticLabel	String?	null	Accessibility label
fit	BoxFit	BoxFit.contain	How the icon fills its bounds
matchTextDirection	bool	false	Mirror the icon in RTL locales

Theming and dark mode

FUI resolves its color and size from the ambient IconTheme, exactly like Flutter's built-in Icon widget. That means icons automatically switch color with your ThemeData in light/dark mode, and you can restyle entire subtrees at once:

IconTheme(
  data: const IconThemeData(color: Colors.teal, size: 32),
  child: Row(
    children: const [
      FUI(RegularRounded.home),
      FUI(RegularRounded.search),
      FUI(RegularRounded.bell),
    ],
  ),
)

Browse all icons

• 🔎 Interactive gallery — search all 2,988 icons and copy the code snippet with one tap.
• 📚 API reference — every constant is documented.
• 🧰 Programmatically — each style class exposes an all map (kebab-case name → asset path), and FuiIcons.styles aggregates the six styles. Handy for building your own icon picker:

// All Regular Rounded icons:
for (final entry in RegularRounded.all.entries) {
  print('${entry.key} -> ${entry.value}');
}

// Every style:
FuiIcons.styles.forEach((styleName, icons) {
  print('$styleName has ${icons.length} icons');
});

Migrating from 2.0.x

Nothing breaks — your existing code keeps compiling. Two things were modernized in 2.1.0:

1. Icon constants are now lowerCamelCase. The old SCREAMING_CASE constants still work but are deprecated and will be removed in 4.0.0:

   FUI(RegularRounded.ADDRESS_BOOK) // deprecated
   FUI(RegularRounded.addressBook)  // ✅ use this
   

2. Icons now follow your theme. When you don't pass a color, the icon uses the ambient IconTheme color (previously it was tinted grey), and the default size honours IconTheme.size (24 in Material apps, previously a fixed 30). Pass color/width/height explicitly if you need the old values.

FAQ

Why don't I see the icon I expect? Check the gallery — names follow the original Flaticon UIcons naming. The same glyph exists in all 6 styles.

Can I use these icons commercially? Yes. The package code is MIT licensed and the icons come from Flaticon's open source UIcons collection. See the attribution note below.

How big is the package? The package bundles all 2,988 SVGs (~12 MB uncompressed) as Flutter assets. A future 3.0.0 release will ship the icons as icon fonts with full tree-shaking, so only the icons you use end up in your app binary. Follow the roadmap for progress.

License and attribution

• Source code: MIT License © Baldomero Cho.
• Icons: UIcons by Flaticon, used under their open source/free license. If you redistribute the icons outside this package, review Flaticon's license terms.

Contributing

Found a bug or want a new feature? Open an issue or a pull request on GitHub. If this package saves you time, a ⭐ on GitHub and a 👍 on pub.dev help others discover it.