How do I write 4, IIII or IV?

The correct form is **IV** (5 minus 1). Four repetitions of the same digit (IIII) were used historically and are common on clocks (better visual symmetry), but formally they're wrong. Rule: the same symbol can't appear more than 3 times in a row. The tool accepts only the correct form IV.

What are the subtractive rules (IV, IX, XL)?

Six allowed pairs, where a smaller numeral before a larger one means subtraction: - **IV** = 4 (5-1) - **IX** = 9 (10-1) - **XL** = 40 (50-10) - **XC** = 90 (100-10) - **CD** = 400 (500-100) - **CM** = 900 (1000-100) Other combinations are wrong, e.g. "IL" for 49 should be **XLIX**.

Because the largest Roman numeral is **M = 1000**, and it can be repeated at most 3 times. **MMMCMXCIX = 3999** is the largest "classic" number expressible in Roman numerals. For larger numbers Romans used a bar over a symbol (meaning multiply by 1000), but that's advanced and less standardized.

Is there a Roman numeral for zero?

**No**. The Romans had no concept of zero as a number. The idea of zero came much later, from India, through the Arabs, into Europe in the Middle Ages. The Roman system is built on adding and subtracting symbols, zero would add nothing, so there's no symbol for it.

Why do clocks show IIII instead of IV?

It's a **clockmaker's convention**, not a math error. IIII at the 4 o'clock position gives better visual symmetry with VIII at 8 o'clock, both have 4 characters. Big Ben and most classic clocks use IIII. It's a **historical style**, not a standard, the tool accepts only the correct IV.

Lowercase or uppercase Roman numerals?

Classically **uppercase** (as on coins and monuments). Modern usage allows both: uppercase for formal entries (chapters, monarch titles), lowercase as auxiliary numbering (e.g. "ii)", "iii)" in an outline). The tool accepts both inputs and outputs uppercase.

How do I write a century, convert from year?

A century is written like a year. XX is the 20th century (1901-2000). Easy rule: take the year's "thousands + hundreds", divide by 100, add 1. Year 1969 → 19 → century 20 (XX). Year 2024 → century 21 (XXI).

Roman Numerals Converter - free

Decimal number (1-3999)

Roman numeral

Symbols

100

500

1000

Examples

How do I write a number in Roman numerals?

Two-way converter, type a regular number and see the Roman numeral (2024 → MMXXIV), or type a Roman numeral and see the regular number (XIV → 14).

The tool validates the Roman numeral: "IIII" is rejected as invalid (the correct form is "IV"). Plus a cheat sheet of symbols (I, V, X, L, C, D, M) and 16 example conversions (1492, 1969, 2024 etc.).

Works for numbers from 1 to 3999, the classic range used by the Romans.

How to use it

Type a regular number (1-3999), get the Roman numeral.

Or type a Roman numeral: get the regular number.

The validator checks correctness: "IIII" is wrong (should be IV), "VL" is wrong (should be XLV), and so on.

Click any example below to load that value, great for learning by trying.

When this is useful

The most common uses:

Book chapters: "Chapter XII", which is that? Type it, get 12.
Dates on historical buildings and coins: "MCMLXIX" on a painting frame or collector's coin. Tool converts it to 1969.
Monarchs and rulers: "Louis XIV", "Henry VIII", "Charles III". The number is a Roman numeral. Easier to say "the eighth" than count tally marks.
Movies and TV series: "Star Wars: Episode IV: A New Hope" is the fourth episode. "Rocky II", "Godfather Part III".
Clocks with Roman numerals: classic wall and mantel clocks often write hours as IV, IX, XII. Sometimes IIII appears instead of IV (a clockmaker's stylistic choice).
Centuries and years: the 20th century is 1901-2000. The 21st century is 2001-2100. Centuries are written in Roman numerals.
Sports events: Super Bowl LVIII is the 58th edition. Olympiad XXXIII is the 33rd edition.
Education, math problems and history lessons: kid has homework "Write 487 in Roman numerals", they can check their answer here.

Questions and answers

Seven basic symbols: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1000. Numbers are formed by combining them (e.g. III = 3, XV = 15, MCC = 1200). Bigger numbers use more symbols.

How do I write a number in Roman numerals?

Two-way converter, type a regular number and see the Roman numeral (2024 → MMXXIV), or type a Roman numeral and see the regular number (XIV → 14).

Works for numbers from 1 to 3999, the classic range used by the Romans.

How to use it

Type a regular number (1-3999), get the Roman numeral.

Or type a Roman numeral: get the regular number.

The validator checks correctness: "IIII" is wrong (should be IV), "VL" is wrong (should be XLV), and so on.

Click any example below to load that value, great for learning by trying.

When this is useful

The most common uses:

Book chapters: "Chapter XII", which is that? Type it, get 12.
Dates on historical buildings and coins: "MCMLXIX" on a painting frame or collector's coin. Tool converts it to 1969.
Monarchs and rulers: "Louis XIV", "Henry VIII", "Charles III". The number is a Roman numeral. Easier to say "the eighth" than count tally marks.
Movies and TV series: "Star Wars: Episode IV: A New Hope" is the fourth episode. "Rocky II", "Godfather Part III".
Clocks with Roman numerals: classic wall and mantel clocks often write hours as IV, IX, XII. Sometimes IIII appears instead of IV (a clockmaker's stylistic choice).
Centuries and years: the 20th century is 1901-2000. The 21st century is 2001-2100. Centuries are written in Roman numerals.
Sports events: Super Bowl LVIII is the 58th edition. Olympiad XXXIII is the 33rd edition.
Education, math problems and history lessons: kid has homework "Write 487 in Roman numerals", they can check their answer here.

Questions and answers

Roman Numerals Converter

How do I write a number in Roman numerals?

How to use it

When this is useful

Questions and answers

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Roman Numerals Converter

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When this is useful

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