Online Calculators
A growing set of simple, exact calculators that run entirely in your browser — work out a percentage, your age to the day, or your BMI in metric or imperial. Each one shows the working, not just the answer, and nothing you type is uploaded or stored.
Compound Interest Calculator
Compound interest with monthly contributions — daily, monthly, quarterly or yearly.
Hours Calculator
Add or subtract hours and minutes, or measure between two times — with decimal hours.
Sales Tax Calculator
Add sales tax to a price — or work backwards from a receipt total to the pre-tax amount.
Percentage Calculator
What is X% of Y · X is what % of Y · percent change between two numbers.
Age Calculator
Exact age in years, months and days — plus total days, weeks and next birthday.
BMI Calculator
Body mass index in metric or imperial, with your WHO category and healthy range.
Loan Calculator
Monthly payment, total interest and total cost from amount, rate and term.
Discount Calculator
Sale price and amount saved from a price and % off — or the % between two prices.
Tip Calculator
Tip, total and per-person share from your bill, tip % and party size.
Date Difference Calculator
Days, weeks and months between two dates — plus working days and a Y/M/D breakdown.