English Club : Learn English : Vocabulary : Numbers : Roman Numerals

On this clockface you see Roman numerals for the hours and Arabic numerals for the minutes.

Roman Numerals

The numbers that we normally use (1, 2, 3 etc) are called "Arabic numerals". But we sometimes use another system for writing numbers - "Roman numerals". The Romans used letters of the alphabet to represent numbers, and you will occasionally see this system used for page numbers, clock faces, dates of movies etc.

The letters used in Roman numerals are:

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

We can use upper-case letters (capitals) or lower-case letters (small letters) when writing Roman numerals. So the following numbers are exactly the same: XVIII = xviii = 18

In general, letters are placed in decreasing order of value, eg XVI = 16. Letters can be repeated one or two times to increase value, eg XX = 20, XXX = 30. Letters cannot be repeated three times, so XXXX is not used for 40. In this case, XL = 40 (50 minus 10).

Look at these examples of Roman numerals in use:

The Introduction is on page vii (= The Introduction is on page 7)

Significant Roman numerals from one to a thousand

Roman Numerals		Arabic Numerals
upper-case	lower-case	Arabic Numerals
I	i	1
II	ii	2
III	iii	3
IV	iv	4
V	v	5
VI	vi	6
VII	vii	7
VIII	viii	8
IX	ix	9
X	x	10
XI	xi	11
XII	xii	12
XIII	xiii	13
XIV	xiv	14
XV	xv	15
XVI	xvi	16
XVII	xvii	17
XVIII	xviii	18
XIX	xix	19
XX	xx	20
XXI	xxi	21
XXII	xxii	22
XXIII	xxiii	23
XXX	xxx	30
XL	xl	40
L	l	50
LX	lx	60
LXX	lxx	70
LXXX	lxxx	80
XC	xc	90
C	c	100
CC	cc	200
CCC	ccc	300
CD	cd	400
D	d	500
M	m	1000

Arabic Numeral > Roman Numeral Converter

You can use the tool below to convert an Arabic numeral into a Roman numeral: