Roman Numerals Converter

About the Roman Numerals Converter

The Roman Numerals Converter allows you to instantly convert between Arabic numbers (1–3999) and Roman numerals. It follows the standard Roman numeral rules and supports accurate conversion in both directions. This tool is ideal for students, teachers, historians, designers, and anyone working with numerical notation in a classical or stylized format.

What You Can Convert

• Arabic → Roman: Convert any number from 1 to 3999 into its Roman numeral equivalent.
• Roman → Arabic: Translate Roman numerals back into modern numeric values.
• Validation: Detects invalid or non-standard Roman numeral formats.
• Instant Results: Results appear immediately as you type.

How Roman Numerals Work

The converter uses the standard Roman numeral system, which is based on additive and subtractive notation:

• I = 1
• V = 5
• X = 10
• L = 50
• C = 100
• D = 500
• M = 1000

Subtractive notation is used for values like IV (4), IX (9), XL (40), XC (90), CD (400), and CM (900).

How to Use the Converter

1. Enter an Arabic number (1–3999) to convert it to a Roman numeral.
2. Enter a Roman numeral to convert it to its numerical value.
3. The converter automatically detects which input you're using.
4. If the Roman numeral is invalid, the tool will display an error message.

Applications of Roman Numeral Conversion

Roman numerals are still widely used in education, history, clock and watch design, book chapters, movie titles, event names (e.g., Super Bowl), and architecture. This converter makes it easy to generate accurate numerals for academic work, visual design, labeling systems, and historical references.

Roman Numeral Conversion Chart (1–3999)

Below is a quick reference chart showing common and structured Roman numeral values.

This chart covers the most important base values used to construct any Roman numeral between 1 and 3999.