How Roman numerals work
Seven symbols: I=1, V=5, X=10, L=50, C=100, D=500, M=1000. They are usually written largest to smallest and added (XVI = 16), except subtractive pairs where a smaller symbol before a larger one subtracts: IV=4, IX=9, XL=40, XC=90, CD=400, CM=900. So 1994 = MCMXCIV, not MDCCCCLXXXXIIII.
Why the range stops at 3999
Classical Roman numerals have no symbol above 1000 and no zero, so 3999 (MMMCMXCIX) is the largest number the standard system writes cleanly. Larger numbers historically used an overline (vinculum) to multiply by 1000 — this converter sticks to the standard system and says so rather than inventing notation.
Frequently Asked Questions
What is 2026 in Roman numerals?
MMXXVI — 2000 (MM) + 20 (XX) + 6 (VI).
Why is 4 written as IV and not IIII?
Subtractive notation: a smaller numeral before a larger one subtracts. IIII appears on some clock faces by tradition, but IV is the standard form.
Can I convert numbers above 3999?
Not in the standard system — there is no standard symbol beyond M (1000) and no zero. This tool enforces 1–3999 honestly instead of guessing.
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