Free Online Calculators
18 Free Tools
Everyday maths without the fuss. Work out a percentage, an average or a ratio, add fractions, find your GPA or the mark you need in a final exam, and count the days between two dates or the working days in a month. There are also calculators for BMI, daily calories, fuel and electricity costs, plus a countdown and a stopwatch. Health results are estimates, not medical advice.
Percentage CalculatorEvery everyday percentage sum in one place: X% of Y, what percent, percentage change, increase or decrease by a percent.Average CalculatorFind the average (mean), median, mode, range and standard deviation of a list of numbers. Weighted averages too.Ratio CalculatorSimplify a ratio, solve a proportion (A:B = C:?), or split an amount by a ratio like 2:3.Fraction CalculatorAdd, subtract, multiply and divide fractions and mixed numbers, simplify them, and turn decimals into fractions.GPA CalculatorWork out your GPA on the 4.0 scale from your grades and credit hours, and your new cumulative GPA.Grade CalculatorWork out your current grade from weighted assignments and exams, and the score you need on the final.BMI CalculatorWork out your body mass index (BMI) and the healthy weight range for your height. For adults 18 and over.Calorie CalculatorEstimate how many calories you burn a day and how many to eat to lose, keep or gain weight.Age CalculatorWork out your exact age in years, months and days, how many days old you are, and how long until your next birthday.Age Difference CalculatorFind the exact age difference between two people in years, months and days.Date CalculatorCalculate days between dates and add or subtract days.Date Difference CalculatorCount the years, months and days between two dates — plus the total weeks, days, hours and minutes.Working Days CalculatorCount the working days between two dates, skipping weekends and public holidays — or add working days to a date.Time CalculatorAdd up hours and minutes, work out the time between two clock times (like a shift), and convert decimal hours.Fuel Cost CalculatorWork out the fuel cost of a car trip from the distance, your car’s fuel economy and the fuel price. Split it between passengers.Electricity Cost CalculatorWork out how much electricity an appliance uses and what it costs per day, month and year.Countdown TimerCount down to any date and time — a holiday, a launch or an exam — in days, hours, minutes and seconds.StopwatchA precise browser stopwatch with start, pause, reset and lap.
Guides
- Unix Timestamps Explained: Seconds, Milliseconds and Time Zones
- VAT, GST and Sales Tax Explained: How to Add or Remove Tax From a Price
- How to Calculate a Rent Increase (Percentage, Monthly and Yearly)
- Exchange Rates Explained: Mid-Market Rates, Spreads and Card Fees
- How to Calculate Overtime Pay: Time and a Half, Double Time and Salaried Workers
- How to Calculate Percentages: Increase, Decrease, Difference and Percent Of
- BMI Explained: How It's Calculated, What It Tells You and Its Limits
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