23 in Roman numerals
23 is written XXIII. In chunks: X (10) + X (10) + I (1) + I (1) + I (1) = 23.
The answer
XXIII
23 in Roman numerals is XXIII.
How XXIII is built
To write it, split 23 into 20 + 3. 20 is XX, 3 is III, so 23 is XX then III: XXIII.
To read it, XXIII has 5 chunks, and none of them is a take-away pair, so every chunk is added.
| Chunk | Worth | Why |
|---|---|---|
| X | 10 | Add |
| X | 10 | Add |
| I | 1 | Add |
| I | 1 | Add |
| I | 1 | Add |
The mistake to watch for
Miscounting the letters in XXIII
XXIII is two X's then three I's, all added together. One letter more or fewer makes a different number: XXII is 22.
Check it with the converter
Change XXIII by one letter to see which number you get. The rule numbers it gives are the three rules on the Roman numerals page.
Converter set to XXIII (23).
Keep going
Questions parents ask
What is 23 in Roman numerals?
23 is XXIII.
What comes before and after XXIII?
22 is XXII and 24 is XXIV.
Does XXIII use subtraction?
No. Every letter in XXIII is the same size as, or smaller than, the letter before it, so you just add them all.
What is the biggest letter in XXIII?
X, which is 10. XXIII has 5 letters.
Careful reading is an 11+ skill
Reading all 5 letters of XXIII in order is the careful checking 11+ papers reward. The free diagnostic covers all four subjects, with no card needed.