What does CDXLVIII mean?

CDXLVIII is the Roman numeral for 448 — 400 + 40 + 5 + 1 + 1 + 1.

How do you write 448 in Roman numerals?

Take the largest value that fits and repeat until nothing is left: CD (400), then XL (40), then V (5), then I (1), then I (1), then I (1). That gives CDXLVIII.

448 in Roman numerals

CDXLVIII

Number (1–3,999 for numerals)

Roman numeral

448 is written CDXLVIII in Roman numerals. That is 6 symbol groups added together, reading left to right from the largest value down.

How it breaks down

CDXLVIII = 400 + 40 + 5 + 1 + 1 + 1 = 448
Group	Value	Subtraction	Running total
CD	400	D − C	400
XL	40	L − X	440
V	5	—	445
I	1	—	446
I	1	—	447
I	1	—	448

Why the smaller symbol comes first

CDXLVIII uses subtractive notation in 2 places: CD means D minus C, or 400; XL means L minus X, or 40. A smaller symbol placed before a larger one is subtracted from it rather than added, which is why IX is nine and not eleven.

Only six such pairs are valid — IV, IX, XL, XC, CD and CM. That restriction is what makes the notation unambiguous: IIII and IC both look like they should work, but neither is standard, and only one spelling of any number is correct.

The symbols

Symbol	Value	Used here
I	1	yes — 3×
V	5	yes — 1×
X	10	yes — 1×
L	50	yes — 1×
C	100	yes — 1×
D	500	yes — 1×
M	1,000	no

The same number, other ways

In words: Four hundred forty-eight
Roman numeral: CDXLVIII
Symbol count: 8 characters
Binary: 111000000
Hexadecimal: 1C0

The numbers either side

Number	Roman numeral
446	CDXLVI
447	CDXLVII
448	CDXLVIII ←
449	CDXLIX
450	CDL

Common questions

What is 448 in Roman numerals?: 448 is CDXLVIII.
What does CDXLVIII mean?: CDXLVIII is the Roman numeral for 448 — 400 + 40 + 5 + 1 + 1 + 1.
How do you write 448 in Roman numerals?: Take the largest value that fits and repeat until nothing is left: CD (400), then XL (40), then V (5), then I (1), then I (1), then I (1). That gives CDXLVIII.

Sources

Calculated on this page — At One Place

How these figures are compiled and checked