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Calculators and Converters

Choose from a multitude of free calculators and converters in the areas of finance, health, cooking, math and science for everyday, general use.

How Much Does a Gallon of Water Weigh?

A gallon of water weighs roughly 8lb, but the precise weight varies according to its level of density, which in turn depends on its storage temperature. Learn more about the weight of water - and try out our water weight calculator and reference chart - when you dip...

How Many Cubic Feet is my Refrigerator?

Measuring the space inside your refrigerator might not be your first choice of activity for a Saturday afternoon, but it has its purposes.Perhaps you're planning to buy a week of meal-prep kits described as fitting in an 18 cubic foot fridge, or you're moving house and need to check that your fridge...

Compound Interest Formula - Explained

An in-depth look at the compound interest formula as we break down how to calculate compound interest. The concept of compound interest is that interest is added back to the principal sum so that interest is earned on that added interest during the next compounding period.

How To Measure Your Waist

Whether you're ordering clothes online, monitoring your weight, or designing a bespoke bucket chair for your space-shuttle to the moon (look, the world is on fire; it's OK to have a plan B), you need to be able to measure your body accurately. Here's how to get the digits for your waist.

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