DTCG format

W3C Design Tokens Community Group format (DTCG) is the canonical interchange format for design tokens. Token systems typically treat a DTCG snapshot as the export source of truth from which every platform format (CSS variables, Tailwind, TypeScript, iOS, Android, Flutter) derives.

The DTCG spec is in draft (currently 2025.10) — practitioner adoption is wide enough that breaking changes face strong pushback, but the format is a Community Group product, not a W3C Recommendation.

When to use

• Authoring a new DTCG file from scratch.
• Migrating an existing token system to DTCG.
• Validating a DTCG file against the spec.
• Transforming DTCG into another format (Style Dictionary, CSS variables, etc.).
• Code review on PRs that change DTCG files.

When NOT to use

• Quick prototypes / single-file tokens that won't be exported across tools. The DTCG ceremony isn't earned at that scope.
• Tools that have their own native format (Tailwind config, native CSS variables in a one-product codebase). DTCG is the interchange format; you don't have to author in it.