8 free tools for everyday conversions and calculations — units, dates, loans, percentages, and time zones.
Some calculations are simple in principle but easy to get slightly wrong by hand — converting between measurement systems, calculating a loan's monthly payment, working out a percentage change, or figuring out what time it is somewhere else in the world. This collection covers the calculations people reach for most often in daily life, schoolwork, and financial planning.
Every calculator here runs on standard, well-established formulas — the same ones used in textbooks and financial references — computed instantly in your browser as you type. No figures you enter are ever transmitted or stored anywhere.
Convert length, weight, temperature, and speed units.
Age CalculatorCalculate exact age in years, months, and days.
Date Difference CalculatorFind the number of days between two dates.
BMI CalculatorCalculate Body Mass Index from height and weight.
EMI / Loan CalculatorEstimate monthly loan installments and total interest.
Percentage CalculatorSolve any percentage, increase, or decrease calculation.
Number to Words ConverterConvert digits into written-out words.
Time Zone ConverterConvert a time between any two time zones.