Free Calculators
Quick, reliable calculators for the numbers everyday life throws at you — money, time, health, school and work. Each one runs entirely in your browser: no account, and nothing you enter is uploaded or stored.
Percentage Calculator
Work out percentages three ways — find a percent of a value, what percent one number is of another, or the percent change between two numbers.
CalculatorsOvertime Calculator
Work out how many overtime hours you've done and what they pay — set your standard hours, hourly rate and overtime multiplier.
CalculatorsGPA Calculator
Add your courses, pick a letter grade and credit hours for each, and get your grade point average on the standard US 4.0 scale.
CalculatorsGrade Calculator
Find out exactly what score you need on your final exam to reach the overall grade you want — enter your current grade, your target and the final's weight.
CalculatorsTime Duration Calculator
Find the time between two clock times — enter a start and end time, subtract a break, and read the duration in hours and minutes, total minutes and decimal hours.
CalculatorsTimesheet Calculator
Add up a week of work hours — enter start, end and break times for Monday to Sunday and get your daily hours, weekly total and gross pay.
CalculatorsSleep Calculator
Find the best time to go to bed or wake up based on 90-minute sleep cycles — so you wake between cycles feeling rested, not groggy.
CalculatorsRunning Pace Calculator
Turn a distance and a time into your running pace per kilometre and per mile, plus speed in km/h and mph — with 5K, 10K, half and marathon presets.
CalculatorsFuel Cost Calculator
Work out how much fuel a trip needs and what it costs — in metric or imperial units, with round-trip and split-between-people options.
CalculatorsSales Tax Calculator
Add sales tax to a price or strip it back out of a gross total — enter an amount and a rate to see the net, the tax and the total instantly.
CalculatorsAspect Ratio Calculator
Find the aspect ratio of any width × height and resize to new dimensions without stretching — with 16:9, 4:3 and more as presets.
CalculatorsAge Calculator
Work out your exact age in years, months and days — plus days to your next birthday.
CalculatorsBMI Calculator
Calculate your Body Mass Index from height and weight in metric or imperial units, with an instant category and scale.
CalculatorsTip Calculator
Work out the tip and split the bill per person in seconds — presets, custom percentages and round-up included.
CalculatorsDiscount Calculator
Find the final price after a discount — or the original price before it — with support for stacked discounts.
CalculatorsVAT / Sales Tax Calculator
Add or remove VAT / sales tax from any price, with the tax amount shown separately and common rate presets.
CalculatorsCountdown to Date
Count down the days, hours and minutes to any date — and share the link.
CalculatorsDate Difference Calculator
Count the days, weeks and months between two dates.
CalculatorsLoan & Mortgage Calculator
Work out monthly payments and see the full amortization schedule — with optional extra payments to find out how much interest you can save.
CalculatorsCompound Interest Calculator
See how your savings grow with compound interest over time — add regular contributions and watch the year-by-year breakdown build up.
CalculatorsTDEE Calculator
Estimate your daily calorie needs from your BMR and activity level, with targets for cutting, maintaining or bulking.
CalculatorsDue Date Calculator
Estimate your due date and see how far along you are — privately, in your browser.
CalculatorsWhat you'll find here
Calculators for money, time, health and school — the questions that come up constantly and deserve a fast, clean answer. The Percentage Calculator handles every phrasing of "what percent…?" in one place. The Loan & Mortgage Calculator shows monthly payments and total interest before you sign anything, and the Compound Interest Calculator shows what saving actually does over the years.
Time questions get their own tools: the Age Calculator down to the day, and the Date Difference Calculator for the span between any two dates.
Why these calculators are different
Every result appears instantly as you type — no submit buttons, no results page stuffed between ads. And everything runs in your browser: your salary, loan amount or weight is never uploaded or stored anywhere. No sign-up, ever.
Each calculator also explains its formula in plain language below the tool, so you're not just getting a number — you can see how it was reached.
Popular picks
- The Tip Calculator splits a bill in seconds.
- The BMI Calculator works in metric and imperial.
- Paid by the hour? The Overtime Calculator and Timesheet Calculator do the payday math.
Pick a calculator below — the answer takes seconds.