Calculators
Arithmetic that is quicker to ask than to do: how many days between two dates, what percent of what, how old somebody is on a given day. Each answers as you type, shows its working so you can check it or paste it into an email, and runs entirely in your browser — the numbers you are working with are nobody else’s business.
14 tools and counting
Age CalculatorAn age calculator: your exact age in years, months and days, from a date of birth.Average CalculatorPaste a list of numbers and get the mean, median, mode, range and spread.Business DaysCount forward or back a number of working days and see where you land.Compound InterestSee what a balance grows to, with regular deposits and any compounding.Date DifferenceCount the days, weeks, months and working days between any two dates.Fraction CalculatorAdd, subtract, multiply and divide fractions, with the answer in lowest terms.GPA CalculatorWork out your GPA properly, weighted by the credits each course is worth.Loan CalculatorThe monthly payment on a loan, and how much of it is interest each year.Percentage CalculatorWork out a percentage of a number, or what changed between two numbers.Ratio CalculatorSimplify a ratio to its lowest terms, or find the missing number in a proportion.Roman NumeralsConvert a number to Roman numerals, or read a numeral back as a number.Time Card CalculatorAdd up a week of shifts, minus breaks, in hours and minutes and decimal hours.Tip CalculatorWork out the tip and split the bill into amounts people can actually pay.VAT CalculatorAdd VAT to a price, or take it back out of one — the sum people get wrong.