Roman Numeral Converter

Roman Numeral Converter

Local Processing

Convert numbers to Roman numerals and back.

How It Works & Processing Standards

Convert numbers to Roman numerals and back.

Tool processing runs in your browser. If you create a calculator or conversion share link, its values are included in the URL. See the privacy policy for account, analytics and advertising data.

Current Limits

  • Maximum input length: 100,000 characters

Choose number → Roman or Roman → number under "Task". Subtractive notation such as IV (4) and IX (9) is used.

What You Can Do

Number → Roman
2026 → MMXXVI (1–3999)
Roman → number
MCMXCIV → 1994. Invalid numerals are reported.

How to Use Roman Numeral Converter

  1. 1
    Choose a taskPick the direction.
  2. 2
    Enter inputNumbers 1–3999, or numerals using I, V, X, L, C, D, M.
  3. 3
    CopyCopy the result.

Examples

This year in Roman numerals
Input: 2026
Result: MMXXVI
Reading a numeral
Input: MCMXCIV
Result: 1994

Common Use Cases

  • Reading clock faces, book chapters or film credit years
  • Engraving dates on tattoos or keepsakes
  • Numbering sections or clauses

Frequently Asked Questions (FAQ)

What about 4000 and above?

Standard notation goes up to 3999 (MMMCMXCIX). Larger numbers need overline notation and are not supported.

Is IIII wrong?

It appears on some clock faces by tradition, but the standard form is IV, which this tool uses.

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