Decimaljs

Decimal.js is a JavaScript library that provides arbitrary-precision decimal arithmetic. Designed to address floating-point inaccuracies in the built-in Number type, it enables exact decimal representation and controlled rounding, making it suitable for financial, scientific, and other precision-critical applications.

The core feature is a Decimal data type that can be constructed from strings or numbers and used with standard arithmetic operations such as addition, subtraction, multiplication, and division. It supports configurable precision and rounding, as well as advanced operations like exponentiation and square roots, with results that can be exact or rounded according to settings.

In addition to arithmetic, decimal.js provides formatting and conversion utilities. Values can be formatted to fixed or scientific notation, and converted to native JavaScript numbers when needed, with explicit awareness of possible precision loss. The API is designed to be fluent and, where possible, chainable, often expressed in code as Decimal('0.1').plus('0.2').

Usage is intended for both Node.js and web browsers. The library supports common module systems (CommonJS, AMD, and ES modules) and is available under an open-source license. Documentation and source code are hosted on a public repository, with community contributions and issue tracking.

Limitations include slower performance compared with native arithmetic and higher memory usage. It is not a drop-in replacement for all numeric operations; developers should evaluate precision requirements and test edge cases, especially when interfacing with existing libraries or exporting results to external systems.