Roman to Integer
Convert Roman Numerals back to standard decimal numbers. Decipher ancient dates and numbers.
Loading Tool...
Applications
Reading ancient inscriptions and monuments, deciphering movie copyright years (MMXXIV), converting clock-face numerals, and understanding academic numbering systems used in outlines, legal documents, and chemistry oxidation states.
The Subtraction Principle
Roman numerals use seven symbols (I=1, V=5, X=10, L=50, C=100, D=500, M=1000). Numbers are formed by combining symbols from largest to smallest. When a smaller symbol appears before a larger one, it is subtracted (e.g., IV = 4). The six subtractive pairs are IV, IX, XL, XC, CD, CM. Standard numerals cannot reuse a symbol more than three times consecutively and cannot exceed 3,999 (MMMCMXCIX).
Fun Fact: The maximum Roman numeral in standard form is MMMCMXCIX (3999). Numbers beyond that used a vinculum — a bar above a letter multiplied its value by 1,000. The Romans themselves often wrote 4 as 'IIII' — the subtractive 'IV' became standard only during the medieval period!
Related Tools
View all toolsBinary Converter
Convert text to binary code (0s and 1s) and vice versa. Understand computer logic and low-level data representation.
Number Base Converter
Convert numbers between Binary, Octal, Decimal, and Hexadecimal systems. A versatile tool for computer science and math.
Hex to Decimal
Convert numbers between Hexadecimal and Decimal formats. Vital for debugging memory addresses and color codes in programming.
Integer to Roman
Convert decimal numbers to Roman Numerals. Useful for dates, copyrights, and stylistic numbering.
Unicode Lookup
Search for Unicode characters and get their code points. Find symbols and emojis easily.
Cooking Measurement Converter
Convert between volume (cups, tbsp, tsp, ml, fl oz), weight (g, oz), and ingredient amounts for cooking and baking. Includes density table for water, milk, flour, sugar, butter, oil, and honey.