Roman Numerals Converter

Convert between Arabic numbers and Roman numerals instantly with our professional tool

2025 =
MMXXV
MCMXC =
1990
CDXLIV =
444

Roman Numerals Chart

The seven basic symbols used in Roman numerals and their values:

I
1
V
5
X
10
L
50
C
100
D
500
M
1000

Common Numbers in Roman Numerals

I
1
II
2
III
3
IV
4
V
5
VI
6
VII
7
VIII
8
IX
9
X
10
XX
20
L
50
C
100
D
500
M
1000
MMXXV
2025

How to Read and Write Roman Numerals

The Basic Rules

Historical Context

Roman numerals originated in ancient Rome and were used throughout the Roman Empire from approximately 500 BC to 1500 AD. While Arabic numerals have largely replaced them for most calculations, Roman numerals remain prevalent in:

Common Mistakes to Avoid

Test Your Knowledge

What is XIV in Arabic numerals?

Frequently Asked Questions

What is the largest number in Roman numerals?
The standard Roman numeral system can represent numbers up to 3,999 (MMMCMXCIX). For larger numbers, ancient Romans used a vinculum (a bar over the numeral) to multiply by 1,000, but this convention isn't universally standardized in modern usage.
Why is 4 written as IV and not IIII?
The subtractive notation (IV for 4) became standard because it's more efficient than additive notation (IIII). However, you'll still see IIII on some clock faces, which is a historical convention dating back to early clockmakers who preferred symmetry with VIII on the opposite side.
Can Roman numerals represent zero or negative numbers?
No, the Roman numeral system has no symbol for zero and cannot represent negative numbers. The concept of zero wasn't introduced to European mathematics until the medieval period through Arabic numerals.
How do you write years in Roman numerals?
Years are written by converting the full number to Roman numerals. For example, 2025 = MMXXV, 1999 = MCMXCIX, and 1776 = MDCCLXXVI. This is commonly seen in movie credits, building inscriptions, and formal documents.
Are there lowercase Roman numerals?
While Roman numerals are traditionally written in uppercase (I, V, X, L, C, D, M), lowercase versions (i, v, x, l, c, d, m) are sometimes used in specific contexts like page numbering in book prefaces or outlines. Both forms follow the same rules.
Why do we still use Roman numerals today?
Roman numerals continue to be used for aesthetic and traditional reasons. They convey a sense of formality, timelessness, and importance. They're especially popular in contexts requiring numbered sequences that won't be used for mathematical operations, such as outlining, naming sequels, and commemorative dates.

Complete Roman Numerals Reference Guide

A comprehensive guide to the most commonly used Roman numerals from 1 to 100, plus important milestone numbers.

Numbers 1-20 in Roman Numerals

I
1 (One)
II
2 (Two)
III
3 (Three)
IV
4 (Four)
V
5 (Five)
VI
6 (Six)
VII
7 (Seven)
VIII
8 (Eight)
IX
9 (Nine)
X
10 (Ten)
XI
11 (Eleven)
XII
12 (Twelve)
XIII
13 (Thirteen)
XIV
14 (Fourteen)
XV
15 (Fifteen)
XVI
16 (Sixteen)
XVII
17 (Seventeen)
XVIII
18 (Eighteen)
XIX
19 (Nineteen)
XX
20 (Twenty)

Numbers by Tens (20-100)

XX
20
XXX
30
XL
40
L
50
LX
60
LXX
70
LXXX
80
XC
90
C
100

Important Milestone Numbers

XXI
21
XXIII
23
XXIV
24
XXV
25
XXXI
31
XXXIII
33
XXXVIII
38
XLV
45
LIX
59
XCV
95
CXXXVIII
138
CXXXIX
139

Numbers by Hundreds

C
100
CC
200
CCC
300
CD
400
D
500
DC
600
DCC
700
DCCC
800
CM
900
M
1000

Years and Dates in Roman Numerals

Roman numerals are commonly used for years in copyrights, monuments, and formal documents:

MCMXC
1990
MM
2000
MMX
2010
MMXX
2020
MMXXI
2021
MMXXII
2022
MMXXIII
2023
MMXXIV
2024
MMXXV
2025

Roman Numerals in Education & Learning

Teaching Resources

Roman numerals are an important part of mathematics education, typically introduced in elementary school. Here's how they're commonly taught:

Common Learning Activities

Real-World Applications

Understanding Roman numerals is valuable because they appear in:

Understanding Each Roman Numeral Symbol

I - The Number One

Value: 1 | The letter I represents one, derived from a single finger or tally mark. It's the most basic Roman numeral and can be repeated up to three times (III = 3). When placed before V or X, it acts subtractively (IV = 4, IX = 9).

Common uses: I, II, III (1, 2, 3), IV (4), IX (9), XI (11), XIX (19)

V - The Number Five

Value: 5 | The letter V represents five, possibly derived from an open hand. V cannot be repeated - to write 10, use X instead of VV. V is never used subtractively.

Common uses: V (5), VI (6), VII (7), VIII (8), XV (15), XXV (25), LV (55)

X - The Number Ten

Value: 10 | The letter X represents ten, possibly from two V's joined together. X can be repeated up to three times (XXX = 30). It's used subtractively before L and C (XL = 40, XC = 90).

Common uses: X (10), XX (20), XXX (30), XL (40), XC (90), XIX (19)

L - The Number Fifty

Value: 50 | The letter L represents fifty. It cannot be repeated and is never used subtractively. L appears in the middle range of Roman numerals (40-90).

Common uses: L (50), LX (60), LXX (70), LXXX (80), XL (40), LIX (59)

C - The Number One Hundred

Value: 100 | The letter C represents one hundred, from the Latin word "centum." C can be repeated up to three times (CCC = 300) and is used subtractively before D and M (CD = 400, CM = 900).

Common uses: C (100), CC (200), CCC (300), CD (400), CM (900), XC (90)

D - The Number Five Hundred

Value: 500 | The letter D represents five hundred. It cannot be repeated and is never used subtractively. D is less commonly seen than other symbols but important for numbers 500-900.

Common uses: D (500), DC (600), DCC (700), DCCC (800), CD (400), MDCCC (1800)

M - The Number One Thousand

Value: 1000 | The letter M represents one thousand, from the Latin word "mille." M can be repeated up to three times in standard notation (MMM = 3000). It's essential for writing years and large numbers.

Common uses: M (1000), MM (2000), MMM (3000), MCMXC (1990), MMXXV (2025)

Most Searched Roman Numerals Explained

  • XXIV (24): The number 24 breaks down as XX (20) + IV (4). Commonly seen in 24-hour time notation and as a popular tattoo representing a special date.
  • XXXI (31): Represents 31, calculated as XXX (30) + I (1). Often used for dates, especially December 31st (New Year's Eve) on formal invitations.
  • XXXIII (33): The number 33, written as XXX (30) + III (3). This number has religious significance and appears in various contexts including Super Bowl XXXIII.
  • XXXVIII (38): Represents 38, broken down as XXX (30) + VIII (8). Commonly used in historical dates and sporting event numbers.
  • XLV (45): The number 45, calculated as XL (40) + V (5), where XL uses the subtractive principle. Important for understanding mid-range Roman numerals.
  • LIX (59): Represents 59, calculated as L (50) + IX (9). This number showcases both addition and subtraction rules working together.
  • XCV (95): The number 95, written as XC (90) + V (5). Demonstrates the subtractive notation XC (100-10) plus additive V.
  • CXXXVIII (138): Represents 138, broken down as C (100) + XXX (30) + VIII (8). A more complex number showing multiple addition operations.
  • CXXXIX (139): The number 139, calculated as C (100) + XXX (30) + IX (9). Similar to 138 but uses the subtractive IX for 9.
  • Why These Numbers Are Popular

    Many people search for specific Roman numerals for practical reasons: