Converta números para e de algarismos romanos
Numbers above 3,999 use vinculum notation: a line above a numeral multiplies its value by 1,000.
So ICCCXXV = 1.000.325.
Did you know?
Fibonacci's Sales Pitch
Fibonacci didn't invent Hindu-Arabic numerals — they originated in India around 500 AD. But his 1202 book Liber Abaci was essentially a 600-page argument that these new numbers were better for business. He showed European merchants how place value and zero could transform trade and banking. He was right. By 1500, the debate was over.
Read more →The Subtraction Rule: Elegant Shorthand
The subtraction rule is what makes Roman numerals clever rather than just tedious. Instead of writing IIII for 4, you write IV: "one before five." Instead of DCCCC for 900, you write CM: "one hundred before one thousand." Only six subtractive pairs exist (IV, IX, XL, XC, CD, CM), and once you know them, you can read any Roman numeral instantly.
Read more →De onde vêm os números romanos?
Acredita-se que os números romanos tenham origem em sinais manuais e marcas de contagem. O traço I representa um dedo, o V representa o espaço entre o polegar e os dedos para o cinco, e o X representa as mãos cruzadas para o dez. As letras L, C, D e M vêm de modificações de letras gregas como chi, theta e phi para representar 50, 100, 500 e 1.000. Com o tempo, essas marcas se transformaram nas letras latinas reconhecidas hoje. Não existe 0 no alfabeto romano, pois o conceito do número 0 só se desenvolveu plenamente depois que a Índia o inventou por volta de 600 d.C. / 10600 HE.