The Roman Numerals Converter converts integers (1–3999) to Roman numerals or decodes Roman numeral strings back to their decimal equivalents. Supports standard subtractive notation — IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900 — and accepts both directions without requiring you to select a mode first.
Roman numerals are still in active use today: clock faces (both traditional IIII and standard IV styles), Super Bowl numbering (Super Bowl LVIII), movie and TV sequel titles, book chapter headings, monarchs and popes (King Charles III, Pope Francis), copyright years in film credits, outline numbering in legal documents and academic papers, and decorative applications in architecture and engraving.
The converter supports all standard values: I (1), V (5), X (10), L (50), C (100), D (500), M (1000), as well as the six subtractive forms that make the system non-trivially non-additive. The maximum representable value is MMMCMXCIX (3,999) — values of 4,000 and above require the non-standard vinculum notation not covered here.
For bulk conversion of many numbers at once, use the tool together with the Add Prefix/Suffix or Find & Replace tools to build a processing pipeline.
All conversion happens instantly in your browser. No sign-up or installation is required.
Enter a number (1–3999) to convert to Roman numerals.
Or enter Roman numerals (e.g. MMXXIV) to convert to a number.
The result is shown instantly.
Copy the result.
Both tools convert a non-digit number representation into standard Arabic numerals, but from different source systems. The Roman Numerals Converter handles the letter-based Roman system (XIV, MMXXIV) still seen on clocks, movie credits, and monuments.
Words to Numbers instead handles English number words found in transcribed speech and formal writing. If you're looking at letters like I, V, X, L, C, D, M, use the Roman Numerals Converter; if you're looking at spelled-out English words, use Words to Numbers.
The maximum in standard Roman numeral notation is 3,999, written as MMMCMXCIX. Numbers of 4,000 and above require the non-standard vinculum (overline) notation, which is not in common use and is not supported here.
Roman numerals use a subtractive convention: when a smaller value appears before a larger one, it is subtracted rather than added. IV means 5 − 1 = 4. The six subtractive forms are IV (4), IX (9), XL (40), XC (90), CD (400), and CM (900).
Clock faces traditionally use IIII rather than IV, partly for visual symmetry (balancing VIII on the opposite side) and partly for historical convention predating the subtractive rule. Both forms are technically acceptable. This converter uses the standard subtractive IV form.
MMXXIV is 2024. MM = 2000, XX = 20, IV = 4. Roman year notation is commonly used in film and TV copyright credits, monument inscriptions, and formal document headers.
The tool converts one number per input. For bulk conversion, copy your number list into the Sort Lines or Add Prefix/Suffix tools to prepare them, or use a spreadsheet formula like =ROMAN(A1) in Excel or Google Sheets for large batches.
Yes — the decoder accepts both uppercase (XIV) and lowercase (xiv) Roman numeral input and converts both correctly. The output for integer-to-Roman conversion is always uppercase, following the conventional typographic standard.
Enter the Roman numeral shown in the credits (e.g. MMXXIV) to decode it back to the standard year (2024). Films often use Roman numerals in copyright notices for a more formal appearance.
Super Bowl numbering started with Super Bowl I in 1967. Decode the Roman numeral here to get the number, then add 1966 to find the year it was played.
Yes — regnal numbers like VIII (King Henry VIII) or XXIII (Pope John XXIII) use the same standard Roman numeral rules and convert correctly with this tool.