Roman Numeral Converter
Range: 1 - 3999
I, V, X, L, C, D, M
Quick Reference Chart
Recent Conversions
Explore More Math Tools
The Complete Guide to Roman Numerals
Roman Numerals are more than just ancient symbols; they are a logic puzzle built into history. From the columns of the Colosseum to the credits of your favorite movie, this system has survived for over 2,500 years. This guide covers everything you need to know to read, write, and understand them like a true Roman.
The 7 Sacred Symbols
The entire system is built on just seven letters from the Latin alphabet. By combining these, you can express any number from 1 to 3,999 in standard notation.
How to Read: The 3 Rules
1. Addition
When a symbol appears after a larger (or equal) one, add it.
2. Subtraction
When a smaller symbol appears before a larger one, subtract it.
3. Repetition
Never repeat a symbol more than 3 times. Use subtraction instead.
The Limit: 3,999
In standard strict Roman numerals, the largest value is MMMCMXCIX (3,999). Why? because there is no standard symbol larger than M (1,000), and you cannot repeat M more than three times (MMM = 3,000). To go higher, Romans used a Vinculum (a horizontal bar) over a number to multiply it by 1,000, but standard computer keyboards don't support this easily!
Modern Usage
- Clocks: "IV" is often written as "IIII" on clocks for symmetry with "VIII". This is known as the "Watchmaker's Four".
- Copyrights: Films often use Roman numerals for release years (e.g., MCMLXXXVIII for 1988) to make the date feel timeless.
Reference Chart
1-100| Decimal | Roman Numeral |
|---|---|
1 | I |
2 | II |
3 | III |
4 | IV |
5 | V |
6 | VI |
7 | VII |
8 | VIII |
9 | IX |
10 | X |
11 | XI |
12 | XII |
13 | XIII |
14 | XIV |
15 | XV |
16 | XVI |
17 | XVII |
18 | XVIII |
19 | XIX |
20 | XX |
Showing 1 to 20 of 102 results
Frequently Asked Questions
How do you write the year 2024 in Roman Numerals?
The year 2024 is written as MMXXIV. Breakdown: MM (2000) + XX (20) + IV (4). This format is commonly used in movie credits and building cornerstones.
Can Roman Numerals be lower case?
Yes! While capital letters (I, V, X) are standard for monuments and titles, lower case (i, v, x) is perfectly valid and often used in pagination (e.g., 'page vi') or outlining.
What is the largest symbol in the standard set?
The largest standard symbol is M, representing 1,000. Without using the Vinculum (bar over the top), you satisfy specific values by repeating M (e.g., MMM for 3,000).
Why is 'LL' not used for 100?
The rule of repetition states that V, L, and D are never repeated. 'LL' would be 50+50, but we have a specific symbol for 100 (C). Only I, X, C, and M can be repeated.
Did Romans have fractions?
Yes, but they were duodecimal (base-12). The most common symbol was 'S' (Semis), representing 1/2. Dots were used to represent twelfths (unciae).
How do you read long Roman Numerals easily?
Break them down by place value from left to right. For MCMLXXXVIII: M (1000), CM (900), L (50), XXX (30), V (5), III (3). Added together: 1988.
Who invented Roman Numerals?
They originated in ancient Rome, evolving from Etruscan numerals between 900 and 800 B.C. They were the standard counting system in Europe for nearly 2,000 years until Hindu-Arabic numerals replaced them.
Why is 99 written as XCIX and not IC?
The subtraction rule has limits. You can only subtract a power of ten (I, X, C) from the next two highest 'levels'. I can only be subtracted from V and X. X can only be subtracted from L and C. Therefore, 99 is 90 (XC) + 9 (IX), never IC.
Why is there no zero in Roman Numerals?
The Romans used numerals for trading and counting goods, where 'zero' (nothing) didn't need a token. They did have a word for it—'nulla' (Latin for 'none')—but no specific symbol like our modern '0', which was introduced later by Hindu-Arabic systems.
What is the rule for 4 (IV vs IIII)?
The standard rule is 'Subtractive Notation', where 4 is written as IV (one before five). However, 'IIII' was commonly used in ancient times and is still standard on clock faces today ('The Watchmaker's Four') to provide visual balance with VIII on the opposite side.
How do you write numbers usually larger than 3,999?
To express large numbers, Romans used a 'Vinculum'—a horizontal bar placed over a numeral to multiply it by 1,000. For example, a V with a bar over it would represent 5,000. Double bars could indicate multiplication by 1,000,000.
Why do we still use Roman Numerals today?
They evoke a sense of tradition, gravitas, and timelessness. That's why they are used for monarchs (Queen Elizabeth II), major recurring events (Super Bowl LVIII), copyright dates in movies, and distinct sections in outlines.