Roman Numeral Converter

The Seven Symbols

Roman numerals use only seven distinct symbols, each with a fixed value:

Every number from 1 to 3,999 is expressed as a combination of these seven symbols, following specific addition and subtraction rules.

How Roman Numerals Work

Addition rule: When a symbol of equal or lesser value follows another, add the values.

• III = 1 + 1 + 1 = 3
• VIII = 5 + 1 + 1 + 1 = 8
• XVII = 10 + 5 + 1 + 1 = 17

Subtraction rule: When a symbol of lesser value appears before a larger one, subtract it. Only six subtractive combinations are used in standard Roman numerals:

Repetition limit: A symbol can repeat at most three times consecutively. That's why IV exists — you can't write IIII. The exception is I, X, C, M — V, L, D are never repeated.

Reading Examples Step by Step

MMXXVI (this very year, 2026):

• MM = 1000 + 1000 = 2000
• XX = 10 + 10 = 20
• VI = 5 + 1 = 6
• Total: 2026

MCMXCIX (1999 — Prince's famous song):

• M = 1000
• CM = 900 (1000 − 100)
• XC = 90 (100 − 10)
• IX = 9 (10 − 1)
• Total: 1999

CDXLVIII (448):

• CD = 400
• XL = 40
• VIII = 8
• Total: 448

Where Roman Numerals Still Appear

Roman numerals didn't disappear with the Roman Empire — they're still used in specific contexts where they convey tradition, formality, or clarity:

Movie sequels and franchises: Star Wars: Episode IV, Rocky IV, Super Bowl LVII. The roman numeral signals that this is part of an established, ongoing series.

Clock faces: Many analog clocks use Roman numerals. Interestingly, clock faces traditionally use IIII instead of IV for the 4 — possibly for visual balance, since the 8 (VIII) has three letters and symmetry looked better with IIII opposite it.

Book chapters and front matter: Page numbers in a book's introduction and preface are typically Roman (i, ii, iii, iv) in lowercase, keeping them visually distinct from the main numbered pages.

Monarchs and popes: King Charles III, Pope Francis the First (but Francis I in formal reference), Elizabeth II. When someone shares a name with predecessors, Roman numerals distinguish them.

Year of production: Film copyright notices (`©...