Unit Converter

About This Tool

This tool provides a general unit conversion engine for numeric values with units. It accepts inputs as value, from_unit, and to_unit, and returns the converted value with the corresponding unit. It supports CSS typography units (em, rem) and common metric/imperial measures, while enforcing dimensional safety.
Conceptually, normalization to base dimensions is followed by application of precise conversion factors, with optional precision control and unit aliases to handle common synonyms. Outputs are deterministic and formatted according to the chosen precision.
Designed for developers embedding calculations in apps, designers validating typography scales, and engineers verifying specifications, it helps ensure consistency across interfaces and documents. Its value lies in predictable behavior, explicit error signaling for incompatible pairs, and support for both typographic and physical units.
Key use cases include validating a CSS-based font-size cascade, converting lengths (mm, cm, m, in, ft), volumes (ml, L), or masses (g, kg) within the same dimension, and providing a safe, auditable calculation trail.

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