Roman Numeral Converter
Convert numbers to Roman numerals or Roman numerals back to numbers instantly with this free converter that runs in your browser.
Enter a number to see its Roman numeral.
Standard numerals cover 1–3999. Runs entirely in your browser.
How to use this calculator
- Choose a direction: Number → Roman, or Roman → Number.
- Type the value — the result updates as you type, with a copy button.
How it works
Roman numerals combine M (1000), D (500), C (100), L (50), X (10), V (5) and I (1), largest first, using subtractive pairs like IV (4) and IX (9).
Standard form covers 1–3999; bigger numbers need an overline (vinculum), which isn't part of everyday usage.
Worked example
2024. = MMXXIV (MM=2000, XX=20, IV=4).
Common mistakes
- Writing IIII for 4 — the correct subtractive form is IV.
- Repeating a symbol more than three times (e.g. XXXX) — use the subtractive pair (XL) instead.
Frequently asked questions
Why only up to 3999?
Without overlines, M (1000) can repeat at most three times, capping standard numerals at MMMCMXCIX = 3999.
Is there a zero in Roman numerals?
No — the Romans had no symbol for zero, so the converter starts at 1.
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Cite this tool
Zerdly. (2026). Roman Numeral Converter. Retrieved from https://www.zerdly.com/tools/roman-numeral-converter/
Tip: Enter any known values to calculate the remaining results.
Designed to run locally in your browser. Tool inputs are not intentionally stored by Zerdly unless stated otherwise.