CXI is the Roman numeral for 111 — 100 + 10 + 1.

How do you write 111 in Roman numerals?

Take the largest value that fits and repeat until nothing is left: C (100), then X (10), then I (1). That gives CXI.

111 in Roman numerals

CXI

Number (1–3,999 for numerals)

Roman numeral

111 is written CXI in Roman numerals. That is 3 symbol groups added together, reading left to right from the largest value down.

How it breaks down

CXI = 100 + 10 + 1 = 111
Group	Value	Subtraction	Running total
C	100	—	100
X	10	—	110
I	1	—	111

No subtraction needed

CXI is purely additive — every symbol is simply added to the one before it, with no subtractive pairs like IV or IX. Numbers avoid subtraction when none of their digits is a 4 or a 9.

The symbols

Symbol	Value	Used here
I	1	yes — 1×
V	5	no
X	10	yes — 1×
L	50	no
C	100	yes — 1×
D	500	no
M	1,000	no

The same number, other ways

In words: One hundred eleven
Roman numeral: CXI
Symbol count: 3 characters
Binary: 1101111
Hexadecimal: 6F

The numbers either side

Number	Roman numeral
109	CIX
110	CX
111	CXI ←
112	CXII
113	CXIII

Common questions

What is 111 in Roman numerals?: 111 is CXI.
What does CXI mean?: CXI is the Roman numeral for 111 — 100 + 10 + 1.
How do you write 111 in Roman numerals?: Take the largest value that fits and repeat until nothing is left: C (100), then X (10), then I (1). That gives CXI.

Sources

Calculated on this page — At One Place

How these figures are compiled and checked