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Convert numbers to Roman numerals and back (1–3,999), with a place-by-place breakdown and a check for non-standard forms like IIII.
Also covers: Roman numeral to number · Number to Roman numerals · Year in Roman numerals · Roman numerals chart
Direction is detected automatically. Lower case is fine. A smaller numeral before a larger one is subtracted (IV = 4, XC = 90); only I, X and C are used that way, and a letter repeats at most three times.
Roman numeral
MMXXVI
Breakdown
Symbols
| Symbol | Value | Subtractive pairs |
|---|---|---|
| I | 1 | IV 4 · IX 9 |
| V | 5 | |
| X | 10 | XL 40 · XC 90 |
| L | 50 | |
| C | 100 | CD 400 · CM 900 |
| D | 500 | |
| M | 1,000 |
The direction is detected automatically, and the breakdown shows each place value.
MMXXVI: MM (2000) + XX (20) + VI (6).
Standard Roman numerals have no symbol above M (1,000) and don't repeat a letter more than three times. Larger numbers used a bar over letters, which has no standard plain-text form.
It's non-standard — the usual form is IV — though clock faces often use IIII. The converter reads it and points out the standard form.
No. The Romans had no numeral for zero.
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