Material Design Icons and Fluent UI Icons are two of the most widely used open-source icon sets. Both are free, both ship framework packages, and both will look perfectly reasonable in a product UI — which is exactly why the choice is annoying. This page puts the two side by side using the actual artwork and the real numbers.
| Material Design Icons | Fluent UI Icons | |
|---|---|---|
| Icons | 14,001 | 20,170 |
| Visual variants per concept | 5 — outlined, rounded, sharp, two-tone and filled | 2 — regular and filled |
| Design grid | 24×24 | 12–48 |
| License | Apache 2.0 | MIT |
| Attribution required | No | No |
| Official React package | @mui/icons-material | @fluentui/react-icons |
Every pair below is the same concept rendered from each library's own source files. This is the part you cannot get from a written review — the difference in stroke weight, corner rounding and optical size is the thing you will actually notice in your interface.
Products that follow Material Design, Android-adjacent apps, and any interface where recognition matters more than distinctiveness. If your users already use Gmail, Drive, or Android, these icons need no explanation.
Consider otherwise if: Google's newer Material Symbols supersedes this set with variable-font icons in a single file. For a less Google-flavoured look, Fluent UI and Carbon are the enterprise equivalents.
Enterprise applications, Microsoft 365 integrations, and products that already follow Fluent or need extremely broad coverage. The count alone means you will rarely need to look elsewhere.
Consider otherwise if: The size is also a drawback — with 20,170 icons, maintaining visual consistency across a product takes more discipline. Lucide and Heroicons are far easier to keep coherent.
Material Design Icons contains 14,001 icons and Fluent UI Icons contains 20,170. Material Design Icons is Google's official icon set, and it is the most widely deployed icon vocabulary on the web. The 14,001 icons follow the Material geometry rules — a 24×24 grid with 2px keypoint padding, straight edges softened by corner radii, and a deliberate, slightly geometric construction.
Fluent UI Icons is Microsoft's icon library for the Fluent Design System, and at 20,170 icons it is the largest set indexed on IconStash. The icons are drawn across multiple sizes from 12px to 48px and in Regular and Filled styles.
Material Design Icons is released under Apache 2.0. No attribution required, but carries an explicit patent grant and requires notice for modified files.
Fluent UI Icons is released under MIT. Commercial use, modification and redistribution with no attribution required.
You do not have to commit to one. IconStash indexes both libraries, so you can search a concept once and see how each set drew it, then export SVG or PNG at any size and colour. Start with Material Design Icons or Fluent UI Icons, or browse every library comparison.
Both have first-party React packages: @mui/icons-material and @fluentui/react-icons. Material has the smaller catalogue, so for a React app the practical difference is coverage and visual style rather than integration effort. Both tree-shake, so bundle size tracks the number of icons you import, not the size of the library.
Material Design Icons has 14,001 icons and Fluent UI Icons has 20,170. Fluent UI Icons is larger by about 44%. Raw count is not the whole story though — a 20,000-icon set with many near-duplicate variants can be slower to search than a tightly edited 2,000-icon set.
You can, but it usually looks wrong. Each library draws to its own grid and stroke weight — Material uses 24×24 and Fluent UI uses 12–48 — so icons from both sit slightly differently next to each other. If you must mix them, keep each library to a distinct area of the interface rather than interleaving them in the same toolbar.
Material Design Icons is Apache 2.0: No attribution required, but carries an explicit patent grant and requires notice for modified files. Fluent UI Icons is MIT: Commercial use, modification and redistribution with no attribution required. Neither requires payment, but attribution rules differ, so check before shipping in a product where credit is inconvenient.
Material Design Icons offers outlined, rounded, sharp, two-tone and filled; Fluent UI Icons offers regular and filled. If you need to express selected and unselected states with the same glyph, the library with more variants saves you from importing a second set.
At 16px, stroke weight and counter size matter more than coverage. Material draws on a 24×24 grid and Fluent UI on 12–48. Libraries that redraw per size rather than scaling — such as Fluent UI — generally hold up best. The reliable test is to preview both at your actual render size, which you can do on any icon page on IconStash.