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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.


What is the Difference Between Nominal, Effective and APR Interest Rates?

Whether you're paying interest on a debt or earning interest on savings and investments, the nominal interest rate is the figure used before considering inflation. Nominal interest rates are the ones advertised on financial products, but once they are adjusted for inflation, these can go up or down ...


How Much Does a Gallon of Water Weigh?

One US gallon of water weighs around 8.33 pounds or 3.78 kilograms at room temperature. The precise weight of water varies according to its level of density, which in turn depends on its storage temperature.You can learn more about the weight of water - and try out our water weight calculator and re...


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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