unacyType-safe unit conversion

Unit, format and type conversion library for TypeScript with full compile-time safety, zero runtime overhead, and auto-composed multi-hop conversions.

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Full compile-time type safety

Prevents invalid value assignments, invalid conversions, and cross-dimension conversions. Can't pass a Fahrenheit value to a Celsius converter.

Unit accessor API

Intuitive registry.Celsius.to.Fahrenheit(value) syntax backed by a typed registry.

Extensible units

Add metadata to units and register new converters dynamically — no explicit type casting needed.

Auto-composition

Multi-hop conversions resolved via a BFS shortest-path algorithm over the registered converter graph.

Tree-shakeable

Export individual unit converters for optimal bundle size in browser builds.

Zero runtime overhead

Type branding uses phantom types with no runtime cost — your converted code pays nothing at runtime.