Roman Numeral Converter

Convert numbers to Roman numerals and back, from 1 to 3,999

Convert

Number

Whole number from 1 to 3,999

Roman Numeral Chart

The seven symbols
Symbol	Value
I	1
V	5
X	10
L	50
C	100
D	500
M	1,000

Common years
Year	Roman numeral
1900	MCM
1990	MCMXC
2000	MM
2010	MMX
2020	MMXX
2025	MMXXV
2026	MMXXVI
2030	MMXXX

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Quick summary

Roman numerals use seven letters — I (1), V (5), X (10), L (50), C (100), D (500) and M (1,000) — written largest to smallest and added together. A smaller symbol placed before a larger one is subtracted, but only in six pairs: IV (4), IX (9), XL (40), XC (90), CD (400) and CM (900). Convert one decimal place at a time: 1994 is 1000 + 900 + 90 + 4 = M + CM + XC + IV = MCMXCIV, and 2026 is MMXXVI. Standard notation covers 1 to 3,999.

Reviewed by Simple Calculators TeamLast reviewed October 29, 2026

How to use this calculator

Choose the direction in Convert: Number to Roman numeral, or Roman numeral to number.
For a number, type a whole number from 1 to 3,999 in Number — for example a year such as 2026.
For a numeral, type it in Roman Numeral using I, V, X, L, C, D and M; upper or lower case both work.
Read the converted value, then check Breakdown and Place values to see how each part adds up.
If an error appears, the numeral is not in standard form — use the chart below to fix repeated or misplaced symbols.

How Roman Numerals Convert

Number to Roman numeral (place value)

N = \text{thousands} + \text{hundreds} + \text{tens} + \text{ones}

N: Whole number from 1 to 3,999
Place values: Write each nonzero place on its own, then join them left to right
Subtractive pairs: IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900

Worked example

Converting 1994

Given: 4 = IV
90 = XC
900 = CM
1000 = M
Calculation: $1994 = 1000 + 900 + 90 + 4 = \text{M} + \text{CM} + \text{XC} + \text{IV}$
Result: 1994 = MCMXCIV

Roman numeral to number

\text{Value} = \sum \text{symbols}, \text{ subtracting a symbol placed before a larger one}

I, V, X, L, C, D, M: 1, 5, 10, 50, 100, 500, 1,000
Smaller before larger: Subtract it (the I in IX); otherwise add it

Worked example

Reading MMXXVI

Given: MM = 2000
XX = 20
VI = 6
Calculation: $\text{MMXXVI} = 2000 + 20 + 6$
Result: MMXXVI = 2026

Frequently asked questions

Why does the converter stop at 3,999?

Standard Roman numerals never repeat a symbol more than three times, and M (1,000) is the largest symbol, so MMMCMXCIX (3,999) is the highest value they can write. Larger numbers were historically marked with a bar over a numeral to multiply it by 1,000 (the vinculum), but that notation was never standardized and does not type as plain text.

Is there a Roman numeral for zero?

No. The Roman system had no symbol for zero and no negative numbers or fractions in this notation, so the converter accepts whole numbers from 1 upward. Medieval scholars sometimes wrote the Latin word nulla or the letter N to mean nothing, but it was not a numeral.

Why is IIII rejected when some clocks use it?

Many clock faces show 4 as IIII by long-standing design tradition, but the standard modern form is IV. This converter only accepts the one standard spelling of each value, so it flags forms like IIII, VX, IC or MMMM rather than guessing what was meant.

How do I write a year like 2026 in Roman numerals?

Split it by place value and convert each part: 2000 is MM, 20 is XX and 6 is VI, so 2026 is MMXXVI. Years in the 1900s start with MCM (1900), which is why 1999 is MCMXCIX. Film credits and building cornerstones often use this format for dates.

Can I subtract any smaller numeral from a larger one?

No. Only I, X and C are ever subtracted, and only from the next two symbols up: I from V and X, X from L and C, C from D and M. That is why 99 is XCIX (90 + 9), not IC, and 49 is XLIX, not IL.

Key terms

Subtractive Notation: Writing a smaller symbol before a larger one to subtract it — limited to IV, IX, XL, XC, CD and CM.
Additive Notation: Symbols written largest to smallest and summed, as in VIII (5 + 1 + 1 + 1).
Place Value: Thousands, hundreds, tens and ones — each converts to its own group of symbols, and the groups are joined in order.
Vinculum: A bar drawn over a numeral to multiply it by 1,000; a historical extension, not part of standard notation.

Methodology, sources & limitations

This page shows the formula, assumptions, and limitations used for this estimate. Rates, thresholds, and other time-sensitive inputs can change, so verify them against the relevant official source before relying on a result.

For our review approach and the primary sources we consult, see the methodology and source policy. If you spot an outdated figure or formula, please contact us with a correction.

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