Number Conversion — Free & Private

Convert units and measurements, currencies and denominations, number bases and Roman numerals.

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Tools in Number Conversion

Unit & Measurement Converter: Precision conversions across length, weight/mass, data storage, speed, and temp.
Currency & Denomination Calculator: Client-side currency conversion with reference rates, reverse calculation, and cash bill breakdown.
Base & Radix Converter: Convert Decimal, Hex, Binary, and Octal with BigInt precision and bit formatting.
Roman Numeral Converter: Convert between Arabic numbers (1-3999) and Roman numerals in either direction.