Roman Numeral ↔ Arabic Number Converter

Bidirectional converter between Roman numerals and Arabic numbers. Supports standard Roman numerals from 1 to 3999 (I to MMMCMXCIX).

Roman Numeral ↔ Arabic Number Converter
Bidirectional converter between Roman numerals and Arabic numbers. Supports standard Roman numerals from 1 to 3999 (I to MMMCMXCIX).

Supported range: 1-3999

Standard Roman notation only

Live result
Review the normalized output, status, and converted value.
ValidSupported range: 1-3999

Arabic Number (1-3999)

2024

Roman Numeral

MMXXIV

Why Roman numerals still show up

Roman numerals are an old numbering system built from I, V, X, L, C, D, and M. They still appear on clock faces, chapter headings, copyright dates, outlines, monarch names, and event editions, so converting them is still a practical task instead of just a history exercise.

What this converter helps with

This tool converts standard Roman numerals and Arabic numbers in both directions, checks whether a numeral uses conventional subtractive notation, and makes it easier to confirm forms such as IV, XL, CM, or MMXXIV. It is designed for the common modern range from 1 to 3999.

When to use it

Use it when you are reading titles, editing lists, checking a year mark, preparing educational material, or validating user input that mixes Roman and Arabic numerals. It is especially useful when you need a quick answer without second-guessing the rules.