Everyday calculators that show the formula

Enter the bill, choose a tip and split it between friends.

See the final price after one or two discounts, with optional sales tax.

Add tax to a price, or remove it from a total you already have.

Enter your cost and your selling price to see profit, margin and markup.

Turn an hourly wage into annual and monthly pay before taxes.

See what an annual salary works out to per hour.

Calculate body mass index from your weight and height.

Estimate how many calories you burn per day.

Find out what you need on the final to get the grade you want.

Estimate the fuel and cost for a drive.