TheCalculatorVault

Math & Everyday Calculators

7 tools

Percentages, dates, ages and everyday math.

Percentages

PercentageWork out what is X% of Y, what percent one number is of another, and the percentage increase or decrease between two values.

Fractions

FractionAdd, subtract, multiply and divide fractions and get the answer in lowest terms, as a mixed number and as a decimal, with the working shown.

Conversions

Roman NumeralConvert numbers to Roman numerals and Roman numerals to numbers (1–3999), with a place-value breakdown, reference chart and validation.

Dates & Age

AgeExact age in years, months and days from a date of birth, plus next-birthday countdown and total days lived.Age DifferenceCompare two birth dates to see the exact age gap between two people, in years, months and days.BirthdayFun birthday facts: zodiac sign, Chinese zodiac, the day of the week you were born, and your milestone birthday dates.GenerationFind which generation you belong to — Gen Z, Millennial, Gen X, Baby Boomer and more — from your birth year.