Everyday Calculators
Practical day-to-day calculators for tipping, splitting bills and working out ages.
Tip Calculator
Work out the gratuity on a bill, the total to pay, and how much each person owes when you split the check.
Open calculatorAge Calculator
Enter a date of birth to calculate exact age in years, months and days as of today or any date you choose.
Open calculatorGoat Gestation Calculator
Enter the date your doe was bred to estimate her kidding due date. Goats carry for roughly 150 days, so the calculator also shows a likely window around that date.
Open calculatorWedding Alcohol Calculator
Estimate how much alcohol to buy for your wedding. Enter your guest count, how long the reception runs and the drink mix to get beer, wine and spirits in purchasable amounts.
Open calculatorPool Salt Calculator
Find out how much salt to add to your saltwater pool to reach your target salinity. Enter your pool volume and current salt level to get the pounds, kilograms and number of 40 lb bags you need.
Open calculatorEgg Hatch Date Calculator
Enter the date you put your eggs in the incubator and choose the bird type to estimate the hatch date. Chicken eggs hatch in about 21 days; the calculator also shows your lockdown date and a likely hatch window.
Open calculatorDog Pregnancy Calculator (Whelping Date)
Enter the date your dog was bred to estimate her whelping (due) date. Dogs are pregnant for about 63 days, so the calculator also shows a likely window and when pregnancy can be confirmed.
Open calculatorCow Gestation Calculator
Enter the date your cow was bred to estimate her calving due date. Cattle carry for roughly 283 days, so the calculator also shows a likely window and a dry-off date for dairy cows.
Open calculatorHorse Gestation Calculator
Enter the date your mare was bred to estimate her foaling due date. Horses carry for roughly 340 days, about 11 months, so the calculator also shows the likely window and the normal range.
Open calculatorPizza Calculator (How Many Pizzas)
Planning a party? Enter how many people you are feeding, how hungry they are and the pizza size to find out how many pizzas to order, with the total slices and any leftovers.
Open calculatorDiscount Calculator (Percent Off)
Find the sale price and how much you save from an original price and a percent off, with an optional sales tax added to the final total.
Open calculatorDog Age Calculator (Dog Years)
Convert your dog's age into human years using a size-aware method, and see the matching life stage from puppy to senior.
Open calculatorHours Calculator
Calculate how many hours are between a start and end time, minus any unpaid break. Useful for timesheets and shift totals.
Open calculatorDate Difference Calculator
Find how much time is between two dates: the total number of days and weeks, plus a calendar breakdown in years, months and days.
Open calculatorFuel Cost Calculator
Estimate what fuel will cost for a trip from the distance, your vehicle's fuel economy and the price of fuel. Switch between US and metric units.
Open calculatorCat Age Calculator (Cat Years)
Convert your cat's age into human years and see the matching life stage, from kitten to senior. Cats mature quickly in their first two years, then age about four human years for each cat year.
Open calculatorHorse Age Calculator (Horse Years)
Convert your horse's age into human years and see the matching life stage. Horses mature fast in their first few years, then age about 2.5 human years for each horse year.
Open calculatorCat Pregnancy Calculator (Kitten Due Date)
Enter the date your cat mated to estimate her kittening (due) date. Cats are pregnant for about 65 days, so the calculator also shows a likely window and when to set up the nesting box.
Open calculatorRabbit Gestation Calculator (Kindling Date)
Enter the date your doe was bred to estimate her kindling (due) date. Rabbits are pregnant for about 31 days, so the calculator also shows a likely window and when to add the nest box.
Open calculatorSheep Gestation Calculator (Lambing Date)
Enter the date your ewe was bred to estimate her lambing (due) date. Sheep carry for roughly 147 days, about five months, so the calculator also shows a likely lambing window.
Open calculatorPig Gestation Calculator (Farrowing Date)
Enter the date your sow was bred to estimate her farrowing (due) date. Pigs are pregnant for about 114 days, the well-known 3 months, 3 weeks and 3 days, so the calculator also shows a likely window.
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