Type "IIII" into most Roman numeral converters and you'll get 4 back — technically the right number, from a form nobody actually uses. Standard notation is IV, using subtraction (5 minus 1) instead of four I's stacked up.
Roman numeral to number, and the standard-form check
This converter validates as it goes — any Roman numeral you type gets converted to a number and immediately converted back, and if that round trip doesn't match your original input exactly, it flags the numeral as non-standard instead of silently accepting it.
Number to Roman numeral, both directions live
Type a number from 1 to 3999 and the Roman numeral field updates instantly — no separate convert button, works the same typing into either field.
What year is MMXXVI
2026, in case you were wondering — a handy way to decode copyright years, clock faces, and movie credits without counting on your fingers.
