Roman Numeral Converter

Convert any number to Roman numerals or any Roman numeral back to a regular number — with a complete reference table and step-by-step breakdown.

The Roman Numeral Converter is a free online tool designed to help you calculate and analyze convert any number to roman numerals or convert roman numerals back to regular numbers instantly. Planning details accurately is crucial for making smart personal or financial decisions, and this calculator provides instant clarity with downloadable PDF reports.

This tool is built to benefit students, teachers, parents, and home cooks who need to verify numerical operations. By showing the complete mathematical formulas and steps, it helps you understand the process rather than just giving a raw final answer. By evaluating these key calculations, you can determine exactly how different inputs affect your results and align them with your direct planning requirements.

Before using this tool, make sure you have your details ready, such as your numbers, fractions, or ratios in the designated input boxes and select your desired calculation method. This ensures the most accurate calculations.

Enter Arabic Number (1 - 3999)

Common Years

2020	MMXX	2021	MMXXI
2022	MMXXII	2023	MMXXIII
2024	MMXXIV	2025	MMXXV
2026	MMXXVI	2027	MMXXVII
2028	MMXXVIII	1994	MCMXCIV

Key Numbers & Rules

I 1
V 5
X 10
L 50

C 100
D 500
M 1000

Subtractive Notation:

I before V or X = 4 (IV) or 9 (IX)

X before L or C = 40 (XL) or 90 (XC)

C before D or M = 400 (CD) or 900 (CM)

Examples

2026 → MMXXVI
1994 → MCMXCIV
XIV → 14
CD → 400

Frequently Asked Questions

How do Roman numerals work?

Roman numerals use seven basic symbols: I (1), V (5), X (10), L (50), C (100), D (500), and M (1000). Numbers are formed by combining these symbols, typically from largest to smallest, adding their values. For example, VI is 6 (5 + 1), and XVI is 16 (10 + 5 + 1).

What is subtractive notation in Roman numerals?

Subtractive notation is used to avoid repeating a symbol four times. If a smaller symbol is placed before a larger one, the smaller value is subtracted from the larger one. For example, IV is 4 (5 - 1), IX is 9 (10 - 1), XL is 40 (50 - 10), XC is 90 (100 - 10), CD is 400 (500 - 100), and CM is 900 (1000 - 100).

What are the limits of the standard Roman numeral system?

Standard Roman numerals only support numbers from 1 to 3,999 (MMMCMXCIX). For numbers 4,000 and larger, the Romans traditionally used a horizontal line (vinculum) over a numeral to multiply its value by 1,000, which is not supported in the standard text representation.

How do I write the current year (2026) in Roman numerals?

The year 2026 is written as MMXXVI. This breaks down into M (1000) + M (1000) + X (10) + X (10) + V (5) + I (1), totaling 2026.

Is there a Roman numeral for zero?

No, the ancient Romans did not have a Roman numeral symbol for the number zero (0). They used the word "nulla" (meaning "none") or simply left a blank space when no value was present.

Why is IIII sometimes used instead of IV on clock faces?

The use of IIII instead of IV on traditional clocks and watches is a long-standing design choice for visual symmetry and historical tradition. It balances the VIII on the opposite side of the clock face and dates back to ancient Roman sundials.