Roman Numeral Converter

Table of Roman numerals from 1 to 100

From 1 (I) to 100 (C). Multiples of 10 are in bold. For a larger number, use the converter above or the 13-value table.

How the Roman numeral converter works

It is a bidirectional converter: type a decimal (1 to 3999) or a Roman numeral and the other field fills in at once, with a breakdown of each symbol. If you paste a non-standard form such as IIII or IL, it shows the value and the canonical spelling (IV, XLIX).

The seven Roman symbols

Every Roman numeral is built from these seven letters. There is no symbol for zero or for negatives.

The 13 values that build any number

With these thirteen blocks — the seven symbols plus the six subtractive pairs — you can write any integer from 1 to 3999. Subtract them from largest to smallest until you reach zero.

How to convert a decimal to Roman

The classroom method is to split the number into thousands, hundreds, tens and units and translate each part with the 13-value table, from largest to smallest.

Example: 2026

2026 = 2000 + 20 + 6:

• 2000 = MM (M twice).
• 0 hundreds: write nothing.
• 20 = XX.
• 6 = VI (V + I).

Result: MMXXVI.

Another case with three subtractive pairs: 1994 = 1000 + 900 + 90 + 4 = M + CM + XC + IV = MCMXCIV.

How to read a Roman numeral

Read left to right. If a symbol is greater than or equal to the next one, add it; if it is smaller, subtract it (only in the six allowed pairs).

Example: MCMXCIV

Group the subtractive pairs first, then add:

• M = 1000.
• CM = 900 (1000 − 100).
• XC = 90 (100 − 10).
• IV = 4 (5 − 1).

Rules for writing them correctly

The current canonical form — the one this converter uses — fits in four rules. If you break them, the number may still be readable, but it is not written correctly.

Only six subtractive pairs

A smaller symbol before a larger one subtracts, and only in these pairs: IV (4), IX (9), XL (40), XC (90), CD (400) and CM (900).

What may be subtracted

I only subtracts from V and X. X only from L and C. C only from D and M. That is why 49 is XLIX and not IL, and 99 is XCIX and not IC. 1999 is MCMXCIX, not MIM.

V, L and D never repeat and never subtract

Double V, L or D already has its own letter (X, C, M). Do not write VV, LL or DD, nor VL for 45 (it is XLV).

At most three identical symbols in a row

I, X, C and M may repeat up to three times: III = 3, XXX = 30. 4 is not IIII, it is IV. 40 is not XXXX, it is XL.

The clock exception: IIII

On many clock faces 4 appears as IIII to balance VIII visually. Off the clock, the standard form is IV. The converter reads IIII, gives you 4 and suggests IV.

Years, centuries and other uses

Today Roman numerals are rarely used for arithmetic: they appear with ordinal value, almost always after the name.

• Centuries: always after the noun and in Roman numerals, never in Arabic digits. Write 21st century as century XXI in Spanish-style usage, not century 21.
• Monarchs and popes: Felipe IV, John XXIII. The numeral comes after the name, with no ordinal superscript.
• Chapters and preliminary pages of a book (preface, table of contents).
• Years on inscriptions, film credits and plaques: MCMXCIX = 1999.
• Clock faces, often with IIII for 4.

Common years in Roman numerals

A year converts like any other integer: split it and translate each part.

Centuries from I to XXI

The century number is the Roman numeral after the word for century. The 21st century runs from 2001 to 2100.

Why the converter only goes up to 3999

Classical notation uses I, V, X, L, C, D and M, and does not allow more than three M in a row. The largest value written that way is 3999 = MMMCMXCIX. From 4000 onward a bar over the symbol (vinculum) multiplies it by 1000; that format is not in this converter.

Roman numerals in Excel

Put the decimal in A2 (an integer from 1 to 3999) or the Roman numeral in B2.

Decimal to Roman

The ROMAN function converts an Arabic number to Roman text: =ROMAN(A2). If A2 is 2026, the result is MMXXVI. The optional second argument changes the style; leave it out for the classic form this converter uses.

Roman to decimal

The inverse is ARABIC (Excel 2013 and later): =ARABIC(B2). If B2 contains MCMXCIV, the result is 1994. It is not case-sensitive.

Frequently asked questions

How high do Roman numerals go?

With the seven classical letters, from 1 (I) to 3999 (MMMCMXCIX). Larger figures used a bar over the symbol, which this converter does not include.

Is there a zero in Roman numerals?

No. The system has no symbol for 0 or for negatives. The letter N (nulla, nothing) was sometimes used, but never combined with I, V, X, L, C, D or M.

Why is 4 written IV and not IIII?

Because a symbol is not repeated more than three times. 4 is written IV (one less than five). On many clocks you will see IIII, to mirror VIII; off the clock face, the standard form is IV.

Why is 49 XLIX and not IL?

I can only subtract from V or X, never from L. 49 is built as 40 + 9: XL + IX = XLIX. The same rule: 99 is XCIX, not IC.

How do you write 2026 in Roman numerals?

MMXXVI: MM (2000) + XX (20) + VI (6). 2024 is MMXXIV and 2025 is MMXXV. Type it in the converter to see the breakdown.

How are centuries written?

With a Roman numeral after the word for century. Do not write century 21. In running text, small caps are often preferred; next to a capitalized name (John XXIII), the numeral stays in full capitals.

How do I convert Roman numerals in Excel?

Decimal to Roman: =ROMAN(A2). Roman to decimal: =ARABIC(B2). Both cover the range 1 to 3999.