Style Dictionary vs Theo: Token Build Tools

If you're implementing design tokens in 2026, you'll encounter two major build tools: Style Dictionary (Amazon) and Theo (Salesforce). Both transform design token JSON into platform-specific formats like CSS variables, SCSS, iOS Swift, and Android XML. But only one is actively maintained with a thriving ecosystem.

Style Dictionary is the industry standard for design tokens in 2026. It has better maintenance, superior documentation, a larger community, and more extensibility. Theo still works, but it's a legacy choice for teams with existing Salesforce infrastructure or established Theo pipelines.

TLDR

Style Dictionary and Theo are design token build systems that transform JSON token files into platform-specific formats. Style Dictionary wins in 2026 due to active maintenance, larger community, better documentation, and superior plugin ecosystem. Use Style Dictionary for new projects. Only choose Theo if you have existing Theo infrastructure or Salesforce-specific requirements.

Key takeaways:

• Style Dictionary has 3,800+ GitHub stars and active maintenance, Theo has 1,900+ stars and slower update cadence
• Both tools consume JSON token files and output CSS, SCSS, JavaScript, iOS, Android formats
• Style Dictionary has better extensibility with custom transforms and formats
• Migration from Theo to Style Dictionary is straightforward—token JSON stays the same, only config changes

What is Style Dictionary?

Style Dictionary is Amazon's open-source design token build system. It takes design tokens stored in JSON format and transforms them into platform-specific code: CSS variables, SCSS variables, JavaScript constants, iOS Swift code, Android XML resources, and more.

Released in 2017 and actively maintained by Amazon's design systems team, Style Dictionary powers design systems at Amazon, Adobe, Salesforce (ironically), Twilio, and hundreds of other companies.

Core features:

• Multi-platform output – One JSON source, outputs for web (CSS/SCSS/JS), iOS (Swift/Objective-C), Android (XML/Compose), and more
• Custom transforms – Write JavaScript functions to transform token values (e.g., px to rem, hex to RGB)
• Custom formats – Output tokens in any file format you need
• Token aliasing – Reference other tokens (e.g., buttonBackground: {value: "{color.primary}"})
• Build-time token manipulation – Filter, sort, or transform tokens before output

Why it's popular: Style Dictionary is framework-agnostic, platform-agnostic, and highly extensible. It's the de facto standard for design token build pipelines.

What is Theo?

Theo is Salesforce's design token tool, originally built to support the Lightning Design System. It also transforms JSON tokens into platform-specific formats.

Released in 2015 and open-sourced by Salesforce, Theo pioneered many design token concepts. However, it receives less frequent updates and has a smaller community compared to Style Dictionary.

Core features:

• Platform outputs – Supports web (CSS/SCSS/JS), iOS, Android, and design tool formats
• Alias/reference support – Similar to Style Dictionary's aliasing
• Custom transforms – Less flexible than Style Dictionary, but possible with plugins
• Design tool integration – Can generate formats for Sketch and other tools

Why it's less popular: Theo was an early leader but has slowed down. The community is smaller, documentation is less thorough, and the plugin ecosystem is limited. Salesforce teams still use it, but most new projects choose Style Dictionary.

Head-to-Head Comparison

Here's how Style Dictionary and Theo compare across key dimensions:

Verdict: Style Dictionary wins on nearly every metric except design tool integration, where Theo has slightly better built-in support for Sketch (though this is offset by Style Dictionary's larger plugin ecosystem for Figma).

Code Comparison: Same Tokens, Different Tools

Both tools consume JSON design tokens and output platform-specific code. Here's how they compare in practice.

Input: Design Token JSON (Both Tools)

Both Style Dictionary and Theo consume the same JSON token format:

{
  "color": {
    "primary": {
      "value": "#3b82f6",
      "type": "color"
    },
    "primaryHover": {
      "value": "#2563eb",
      "type": "color"
    }
  },
  "spacing": {
    "small": {
      "value": "8px",
      "type": "dimension"
    },
    "medium": {
      "value": "16px",
      "type": "dimension"
    }
  }
}

Style Dictionary Config

Style Dictionary uses a config.json file to define transforms and output formats:

{
  "source": ["tokens/**/*.json"],
  "platforms": {
    "css": {
      "transformGroup": "css",
      "buildPath": "build/css/",
      "files": [
        {
          "destination": "variables.css",
          "format": "css/variables"
        }
      ]
    },
    "js": {
      "transformGroup": "js",
      "buildPath": "build/js/",
      "files": [
        {
          "destination": "tokens.js",
          "format": "javascript/es6"
        }
      ]
    }
  }
}

Build command:

npm install style-dictionary
npx style-dictionary build

Output (CSS):

:root {
  --color-primary: #3b82f6;
  --color-primary-hover: #2563eb;
  --spacing-small: 8px;
  --spacing-medium: 16px;
}

Theo Config

Theo uses a .theo config file or JavaScript configuration:

// theo-config.js
module.exports = {
  transform: {
    type: 'web',
    file: 'tokens/tokens.json'
  },
  format: {
    type: 'css',
    file: 'build/variables.css'
  }
};

Build command:

npm install theo
npx theo theo-config.js

Output (CSS):

:root {
  --color-primary: #3b82f6;
  --color-primaryHover: #2563eb;
  --spacing-small: 8px;
  --spacing-medium: 16px;
}

Key Differences:

1. Config structure – Style Dictionary uses JSON with platform-specific build paths. Theo uses JavaScript config with simpler structure.

2. Naming conventions – Style Dictionary automatically converts camelCase to kebab-case for CSS. Theo preserves naming from token JSON.

3. Extensibility – Style Dictionary makes it easier to add custom transforms. Theo requires more boilerplate for custom logic.

For detailed Style Dictionary implementation, see our Style Dictionary design tokens guide.

When to Use Style Dictionary

Choose Style Dictionary if:

• You're starting a new design token pipeline
• You need multi-platform support (web + mobile)
• You want a large plugin ecosystem and active community
• You need custom transforms or formats
• You prefer well-documented tools with frequent updates

Style Dictionary is the safe default choice in 2026. It has momentum, community support, and Amazon's backing. Unless you have a specific reason to choose Theo, go with Style Dictionary.

When Theo Still Makes Sense

Choose Theo if:

• You have an existing Theo pipeline that works well
• You're building within the Salesforce ecosystem
• You need tight integration with Sketch (legacy design tools)
• You have Theo expertise on your team and don't want to retrain

Theo isn't bad—it's just less actively developed. If you already use Theo and it meets your needs, there's no urgent reason to migrate. But for new projects, Style Dictionary is the better bet.

Migration from Theo to Style Dictionary

If you're considering migrating from Theo to Style Dictionary, the good news is that your token JSON files remain mostly unchanged. Both tools use similar token structures.

Migration steps:

1. Keep your token JSON files – Both tools consume JSON tokens, so your source data stays the same.

2. Convert aliases – Theo and Style Dictionary both support token references, but syntax may differ slightly. Verify your alias syntax matches Style Dictionary's {token.path} format.

3. Rewrite config file – Replace Theo config with Style Dictionary config.json following the platform-specific structure shown above.

4. Update build scripts – Change npx theo commands to npx style-dictionary build in package.json.

5. Test output – Verify generated CSS/SCSS/JS matches your previous Theo output.

Estimated migration time: 2-4 hours for a typical design system with 100-200 tokens.

For converting tokens to JSON format used by both tools, see our design tokens JSON guide.

Verdict: Style Dictionary Wins in 2026

Style Dictionary is the clear winner for design token build systems in 2026. It has better maintenance, larger community, superior extensibility, and broader platform support. Theo was a pioneer, but it's now a legacy choice.

Our recommendation:

• New projects → Use Style Dictionary
• Existing Theo projects → Stay with Theo if it works, but plan to migrate eventually
• Enterprise teams → Style Dictionary (larger community reduces bus factor risk)

The design token ecosystem has consolidated around Style Dictionary as the industry standard. Unless you have Salesforce-specific requirements, there's no reason to choose Theo over Style Dictionary in 2026.

FAQ

Q: Should I use Style Dictionary or Theo for design tokens in 2026?

A: Use Style Dictionary. It has active maintenance, a larger community, better documentation, and more platform outputs. Theo is less actively maintained and has a smaller ecosystem. Unless you have an existing Theo pipeline or Salesforce-specific requirements, Style Dictionary is the better choice for new projects in 2026.

Q: Can I migrate from Theo to Style Dictionary?

A: Yes, migration is straightforward. Both tools consume JSON design token files, so your token source data remains the same. The main changes are the config file format and build script commands. Convert Theo aliases to Style Dictionary references, update your config.json structure, and adjust your build scripts to use the Style Dictionary CLI instead of Theo.

Q: Does Style Dictionary have better community support than Theo?

A: Yes, significantly. Style Dictionary has 3,800+ GitHub stars vs Theo's 1,900+, more frequent releases, more npm downloads per week, and a larger ecosystem of plugins and community transforms. Style Dictionary is maintained by Amazon with consistent updates, while Theo receives less frequent updates from Salesforce.