units documentation

The manual for the units library, grouped by what you are trying to do. Every code snippet in these pages compiles under C++23; the runnable ones are drawn from examples/, and the compiler diagnostics shown are captured verbatim from the compilers.

Start with Getting started; the cheat sheet is the API on one page.

Learn

• Getting started
• First quantities
• Unit conversions

Explain

• Why units
• Dimensional analysis
• Type safety
• CTAD and ADL
• Efficiency
• Scales
• Affine temperature
• Namespaces
• Named-type internals
• Naming computed results consistently

How-to

• Defining new units
• Math functions
• chrono interop
• Serialization
• JSON serialization
• Eigen interoperability
• Disabling iostream
• Subset headers for compile time
• Debugger visualizers
• CMake integration

Reference

• Cheat sheet
• Supported units
• Constants
• Literals
• Type traits
• Concepts
• Configuration macros

Meta

• FAQ
• Migrating from 2.x
• Changelog

The generated API reference (classes, namespaces, the full unit list) is published at https://nholthaus.github.io/units/.