Calculators

Practical number and date calculators with instant browser-local results.

Age Calculator

Calculate exact age, total months, weeks, days and the next birthday.

GPA Calculator

Calculate a credit-weighted grade point average for a set of courses.

Calorie and TDEE Calculator

Estimate adult resting energy expenditure and daily maintenance calories from age, sex, height, weight and activity.

Body Fat Calculator

Estimate body fat percentage from height and circumference measurements using the U.S. Navy method.

Ovulation Calculator

Estimate an ovulation date and six-day fertile window from a regular menstrual cycle.

Macro Calculator

Convert a daily calorie target and macronutrient percentages into grams of protein, carbohydrate and fat.

Julian Date Calculator

Convert a UTC Gregorian date and time into Julian Date, Modified Julian Date and day-of-year values.