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    Roman Numerals: A Complete Guide to Reading and Writing

    UnitConvertLab Team
    2026-06-20
    5 min read

    The Seven Basic Symbols

    • I = 1
    • V = 5
    • X = 10
    • L = 50
    • C = 100
    • D = 500
    • M = 1000

    The Rules of Subtraction

    Romans didn't like having four of the same symbol in a row. Instead of IIII, they used IV (1 before 5).

    • IV = 4
    • IX = 9
    • XC = 90
    • CM = 900

    Modern Uses

    We still use them for:

    • Years (copyright dates on movies)
    • Monarchs (Queen Elizabeth II)
    • Clock faces
    • Page numbers in book prefaces

    Key Takeaways

    • Symbols are generally added (LX = 60)
    • A smaller symbol before a larger one is subtracted
    • There is no zero in Roman numerals!

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