Roman Numeral Converter
Convert between Arabic numerals and Roman numerals (I, V, X and more). Supports 1-3999 and tolerates non-standard forms like clock-face IIII.
Done
Roman Numeral Converter
How to use
- 1
Enter a number
Type an Arabic numeral (e.g. 2026) or a Roman numeral (e.g. MMXXVI).
- 2
Auto conversion
The result appears automatically as you type.
- 3
Copy
Copy the converted value and use it wherever you like.
Features
- Two-way conversion between Arabic and Roman numerals
- Supports integers from 1 to 3999 with subtractive notation (IV=4, IX=9)
- Tolerates non-standard forms such as clock-face IIII (= 4)
- Your numbers are never sent to a server
Use cases
Chapter numbers in books
Check Roman numeral chapter numbering (Chapter I, II, III) for books and documents.
Clock faces
Verify the numerals I-XII on analog clock faces and practice telling the time.
English study and year notation
Learn Roman numerals the way they appear in years, ordinals and everyday English materials.
Details
Roman numerals originated in ancient Rome and are still used for book chapters, clock faces, regnal years, tables of contents, and movie sequels. They combine seven symbols: I=1, V=5, X=10, L=50, C=100, D=500 and M=1000.
This tool converts integers between 1 and 3999 in both directions. It supports subtractive notation such as IV for 4 and IX for 9 — for example, 2026 is written MMXXVI. Non-standard forms like clock-face IIII (= 4) are also interpreted leniently.
All conversion happens in your browser — the numbers you enter are never sent to a server. Type digits and the tool converts to Roman numerals; type letters and it converts back to Arabic.
FAQ
Is 4 written "IV" or "IIII"?
The standard form is "IV", but clock faces sometimes use "IIII". This tool interprets both as 4.
Can I convert 4000 or above?
No. This tool covers the standard Roman numeral range of 1-3999. Values above 3999 show an error.
How do you write 2026 in Roman numerals?
2026 is MMXXVI (2000 = MM, 20 = XX, 6 = VI).
Is my number sent anywhere?
No. All conversion happens locally in your browser.
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All processing happens in your browser. Your files are never uploaded.
Did you know?
In Roman numerals, C stands for 100 and M for 1000, both from Latin (centum and mille).