A line over a numeral multiplies it by 1,000.
Type a Roman numeral such as MCMXCIV and get 1994, with the value of each part. The checker also flags numerals that break the rules, like IIII, VV or IC, and shows the standard spelling (IV, X, XCIX).
How to use
- Type a number such as 1999 to get MCMXCIX, or type a Roman numeral to get its value. The direction is detected automatically.
- Tap any result row to copy it: the numeral, lowercase, Unicode characters or the breakdown.
- Switch to Date to turn a birthday or wedding date into Roman numerals, with your choice of order and separator.
- Open Chart for every numeral from 1 to 100 or 1 to 1000.
- Basic symbols: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1000.
- A smaller symbol before a larger one is subtracted, but only in six pairs: IV (4), IX (9), XL (40), XC (90), CD (400) and CM (900).
- From 4,000 the vinculum is used: a line over a numeral multiplies it by 1,000, so 5,000 is V̅. Copied text uses the combining overline character.
- Invalid numerals such as IIII, VV or IC are flagged with the rule they break and the correct spelling.
How Roman numerals work
Seven symbols carry the values: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500 and M = 1000. You write a number place by place from the largest value, so 2024 = MM (2000) + XX (20) + IV (4) = MMXXIV.
A smaller symbol in front of a larger one is subtracted, but only in six pairs: IV (4), IX (9), XL (40), XC (90), CD (400) and CM (900). That is why 99 is XCIX and not IC, and 1990 is MCMXC rather than MXM.
Common mistakes
No symbol repeats more than three times in a row in the standard form, so 4 is IV and 40 is XL. V, L and D are never repeated or subtracted. Clock faces that show IIII and some old inscriptions break these rules on purpose; the converter accepts them only with a warning and the standard spelling.
Large numbers and dates
Classical numerals stop at MMMCMXCIX (3,999). For larger values a line over a numeral multiplies it by 1,000, so 5,000 is V̅ and 10,000 is X̅. Dates are converted part by part, which is why a wedding date such as 21.06.2025 becomes XXI.VI.MMXXV.
Frequently asked questions
What is 2025 in Roman numerals?
2025 is MMXXV: MM for 2000, XX for 20 and V for 5.
Why is 4 written IV and not IIII?
Standard notation uses subtraction for 4 and 9, so I before V means 5 − 1. IIII is an older additive form still seen on many clock faces.
What is the largest Roman numeral?
Without special marks the largest is MMMCMXCIX, 3,999. With the vinculum, a bar that multiplies by 1,000, this converter goes up to 3,999,999.
Is there a Roman numeral for zero?
No. The Romans had no symbol for zero; medieval writers sometimes used the word nulla or the letter N. The converter accepts numbers from 1.
How do I write a date in Roman numerals?
Convert the day, month and year separately and join them with dots or dashes: 14.02.2015 is XIV.II.MMXV. Use the Date mode to choose the order and separator.
How do I read a long numeral like MCMLXXXIV?
Split it into place values from the left: M (1000), CM (900), LXXX (80), IV (4). Adding them gives 1984.