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Head-to-head · Color Palette Generators

Fluent UI Theme Designer vs Leonardo

  • Updated Oct 2026
  • Both researched from official sources
  • 5 checks side by side
Higher score Fluent UI Theme Designer #3 in Color Palette Generators 8.7/10 Open source ✓ 1 of 5 features Visit site
Leonardo #7 in Color Palette Generators 7.6/10 Open source ✓ 3 of 5 features Visit Leonardo

Fluent UI Theme Designer leads on 0 checks, Leonardo on 1, and 4 are even. Who comes out ahead on the 5 yes/no, price and count checks where we have data for both products. The editor score weighs everything else too.

Our verdict

  • Highest scoreFluent UI Theme Designer · 8.7/10
  • Most featuresLeonardo · 3 of 5

Fluent UI Theme Designer scores higher on our rubric for color palette generators: 8.7 against 7.6 out of 10; our editors rank them #3 and #7.

On palette methods, Leonardo gives you Both where Fluent UI Theme Designer offers Generate. Leonardo offers image extraction; Fluent UI Theme Designer doesn't.

Fluent UI Theme Designer is the better fit for fluent UI developers creating semantic themes. Leonardo is the better fit for developers building accessible adaptive color systems.

  • Fluent UI Theme Designer fits best

    Fluent UI developers creating semantic themes

  • Leonardo fits best

    Developers building accessible adaptive color systems

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Side by side

Feature Fluent UI Theme Designer 8.7/10 Visit ↗ Leonardo 7.6/10 Visit ↗
At a glance
Editor score 8.7 7.6
Ranking #3 in Color Palette Generators #7 in Color Palette Generators
Best for Fluent UI developers creating semantic themes Developers building accessible adaptive color systems
Pricing model Free Free
Starting price Open source Open source
Free plan Not checked yet Not checked yet
Free trial — —
Deployment Cloud Cloud, Self-hosted
Platforms Web Web
Support Community, Docs Docs
Built for Solo, Small business, Mid-market, Enterprise Solo, Small business, Mid-market, Enterprise
Features Fluent UI Theme Designer 1/5 · Leonardo 3/5
Image extraction — ✓ (best)
Accessibility checks ✓ ✓
Saved palettes — Not checked yet
Brand color library — Not checked yet
Print color support Not checked yet ✓ (best)
Specs
Palette methods Generate Both
Export formats Code, JSON, PowerShell SVG, Tableau (XML), CSS, JavaScript, design tokens, CSV
Our review
Pros
  • Generates Fluent UI palettes and semantic theme slots
  • Previews themed components and checks contrast ratios
  • Exports JavaScript, TypeScript, JSON, PowerShell, and CodePen examples
  • Generates adaptive themes and contrast-ratio-based palettes
  • Checks WCAG compliance and simulates color-vision deficiencies
  • Exports to CSS, JavaScript, SVG, Tableau XML, and design tokens
Cons
  • Does not extract palettes from images
  • Does not save palettes
  • Focused on Fluent UI React rather than general palette generation
  • Its technical breadth may exceed the needs of simple palette selection
  • Self-hosting and API options require a more technical workflow
  • Focused on color systems rather than broader design collaboration
Our verdict

Fluent UI Theme Designer is a browser-based, open-source theming utility for developers and designers working with Microsoft’s Fluent UI React components. It lets users adjust primary, text, and background colors, then inspect the…

Read the review →

Leonardo is an Adobe open-source web application and JavaScript library for creating adaptive color themes, contrast-based palettes, and data-visualization scales. It is aimed at designers and engineers who need color systems that respond…

Read the review →
  1. Fluent UI Theme DesignerColor Palette Generators 8.7Open source
  2. LeonardoColor Palette Generators 7.6Open source

Strengths and trade-offs

  • Fluent UI Theme Designer — where it wins

    • Generates Fluent UI palettes and semantic theme slots
    • Previews themed components and checks contrast ratios
    • Exports JavaScript, TypeScript, JSON, PowerShell, and CodePen examples

    Where it doesn't

    • Does not extract palettes from images
    • Does not save palettes
    • Focused on Fluent UI React rather than general palette generation

  • Leonardo — where it wins

    • Generates adaptive themes and contrast-ratio-based palettes
    • Checks WCAG compliance and simulates color-vision deficiencies
    • Exports to CSS, JavaScript, SVG, Tableau XML, and design tokens

    Where it doesn't

    • Its technical breadth may exceed the needs of simple palette selection
    • Self-hosting and API options require a more technical workflow
    • Focused on color systems rather than broader design collaboration
  • Fluent UI Theme Designer8.7/10 · Open source

    A focused web tool for building accessible Fluent UI semantic themes.

    Visit siteFull verdict →
  • Leonardo7.6/10 · Open source

    A technical palette toolkit for adaptive themes, accessibility, and data visualization.

    Visit LeonardoFull verdict →

More comparisons

All color palette generators comparisons → · Full ranking →

Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

Last updated · How we research and update