XX is a single Roman symbol group for 20.
How 20 is written in Roman numerals
The number 20 is written XX in Roman numerals. Roman numerals use seven letters — I (1), V (5), X (10), L (50), C (100), D (500) and M (1000) — combined from largest to smallest, with subtractive pairs such as IV (4) and IX (9). Need another number? Use the Roman numeral converter or see the 1–100 chart.
Building XX step by step — take the largest value that fits, write its symbol, subtract, repeat.
| Write | Value | Remaining before | Remaining after |
|---|
| X | 10 | 20 | 10 |
| X | 10 | 10 | 0 |
Where you see XX
Regnal and papal names use it the same way — a 20th ruler of a name is styled XX, as in Louis XX or Pope John XX. The 20th Super Bowl was Super Bowl XX; the NFL has used Roman numerals for every edition except Super Bowl 50.
Nearby numbers
Popular numbers in Roman numerals
Frequently Asked Questions
What is 20 in Roman numerals?
20 in Roman numerals is XX. Reading it left to right gives X (10) + X (10) = 20. The number below it, 19, is written XIX, and the number above it, 21, is written XXI.
How do you write 20 in Roman numerals?
Write 20 as XX, combining X (10) + X (10). Roman numerals are built by taking the largest value that still fits, writing its symbol and subtracting it, which reduces 20 in 2 steps: X leaves 10, X leaves 0. Every symbol keeps the same value wherever it stands, so the order is fixed and XX is the only standard spelling of 20.
What are the Roman numerals either side of 20?
Either side of 20 the Roman numerals are XIX for 19 and XXI for 21, with XX between them. Those three numerals are 3, 2 and 3 letters long, so the length changes as you count. Roman numerals have no digit positions, so each step can rewrite the numeral rather than bumping a single digit.
Will the Roman numeral converter accept XX?
Yes, type XX into the Roman numeral converter and it returns 20. The converter takes only the letters I, V, X, L, C, D and M, and it re-encodes whatever you enter and compares it with the standard spelling, so a non-standard form such as IIII is rejected rather than accepted quietly. Its working range runs from 1 to 3999, which covers 20.