Roman Numeral Converter
Convert numbers to Roman numerals and Roman numerals back to numbers (1–3999).
Options
Input
- Characters:
- 0
- Words:
- 0
- Lines:
- 0
Output
- Characters:
- 0
- Words:
- 0
- Lines:
- 0
What Is the Roman Numeral Converter?
The Roman Numeral Converter turns ordinary numbers (1–3999) into Roman numerals and decodes Roman numerals back into numbers. It validates input and converts each line separately, so you can batch a list. Processing is entirely local.
How It Works
Pick a direction. In Number → Roman mode, enter whole numbers from 1 to 3999. In Roman → Number mode, paste Roman numerals (I, V, X, L, C, D, M). Results appear instantly, with clear messages for anything out of range.
When to Use It
Use it for clock faces, book chapters, movie sequels, copyright years, outlines and tattoos — anywhere Roman numerals appear.
Frequently Asked Questions
- Why only up to 3999?
- Standard Roman numerals top out at 3999 (MMMCMXCIX); larger values need overlines that don't display reliably as text.
- Is it case sensitive?
- No. Roman numerals are accepted in upper or lower case when decoding.
Last reviewed: 2026-06-27
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