Roman Numeral Converter — number ⇄ roman
Convert numbers to Roman numerals and back, instantly in your browser.
🔒 Runs entirely in your browser. Your input and output are never sent to a server or stored — fully private.
Type in either field — the other updates live.
About this tool
This converter turns ordinary numbers into Roman numerals and Roman numerals back into numbers, instantly as you type. Enter 2026 to get MMXXVI, or paste a numeral like MCMLXXXIV to read its value — handy for clock faces, book chapters, movie credits, copyright years and tattoos. It all happens in your browser.
Frequently asked questions
How do Roman numerals work?
Roman numerals combine seven letters — I, V, X, L, C, D and M — for 1, 5, 10, 50, 100, 500 and 1000. Letters are added when written largest-first, and a smaller letter before a larger one means subtraction, so IV is 4 and IX is 9.
What numbers can it convert?
Standard Roman numerals run from 1 to 3999, because there is no classical symbol for larger values or for zero and negative numbers. Within that range the converter produces the conventional, widely accepted form.
Is my data sent anywhere?
No. The conversion runs entirely in your browser, so whatever you enter stays on your device.