Free Online Calculators
Accurate calculators for students and health. Each one explains its formula with a worked example you can check by hand.
Student calculators
Calculators โ- ๐ Pomodoro Timer25/5 focus timer with automatic breaks.
- โ๏ธMultiplication ChartTimes tables 1โ12 (up to 20), printable.
- ๐GPA CalculatorWork out your semester and cumulative GPA on the 4.0 scale, weighted or unweighted.
- ๐CGPA CalculatorCombine semester SGPAs into your CGPA and convert CGPA to percentage.
- ๐ฏFinal Grade CalculatorSee the score you need on your final exam.
- ๐Standard Deviation CalculatorMean, median, variance and standard deviation.
- ๐ฌScientific Notation ConverterConvert numbers to and from scientific notation.
- โFraction to Decimal ConverterFractions, mixed numbers, decimals and percentages.
- ๐ Attendance CalculatorCheck your attendance % and how many classes you can miss.
- ๐ Percentage to Letter GradeConvert a percentage to a letter grade and GPA points.
Health & fitness
Calculators โ- โ๏ธBMI CalculatorCheck your body mass index in kg/cm or lb/ft and see your healthy weight range.
- ๐ฅTDEE & BMR CalculatorDaily calorie needs and basal metabolic rate.
- ๐ฅMacro CalculatorSplit calories into protein, carbs and fat.
- ๐๏ธOne Rep Max CalculatorEstimate your 1RM and training percentages.
- ๐ดSleep CalculatorBest bedtime or wake-up time using 90-minute cycles.
- ๐คฐPregnancy Due Date CalculatorEstimated due date and current week of pregnancy.
- ๐Running Pace CalculatorPace per km/mile, speed and race predictions.
- ๐Body Fat CalculatorEstimate body fat % with the US Navy tape method.
- ๐๏ธIdeal Weight CalculatorIdeal body weight using 4 medical formulas.
- ๐งWater Intake CalculatorHow much water to drink per day.
Money & percentages
Money Calculators โ- ๐Compound Interest CalculatorSee how savings grow with monthly deposits.
- ๏ผ Percentage CalculatorX% of Y, percentage change, increase and decrease.
- ๐ฆLoan CalculatorMonthly payment, total interest and schedule.
- ๐Zakat CalculatorWork out zakat on savings, gold and silver.
- ๐ท๏ธDiscount CalculatorSale price, savings and stacked discounts.
- ๐ผSalary to Hourly CalculatorConvert hourly, monthly and yearly pay.
- ๐ฝ๏ธTip CalculatorWork out the tip and split the bill.
By Shah Rukh, software developer ยท Last updated:
About these calculators
Student calculators use the standard credit-weighted and statistical formulas and point out where schools differ. Health calculators use published, peer-reviewed equations: Mifflin-St Jeor for BMR and TDEE, the US Navy method for body fat, and World Health Organization BMI categories. They give estimates, not medical advice.
Looking for dates, countdowns or time zones? See the date & time tools. Zodiac and numerology live in fun tools.
๐ Guides
What Is a Good GPA?
GPA ranges for high school, college, grad school and jobs, and how to raise yours.
How to Calculate GPA
The formula, the 4.0 scale and worked examples for semester, cumulative and weighted GPA.
Weighted vs Unweighted GPA
How honors and AP classes change your GPA, with a worked example.