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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 ...

Density Formula - How To Calculate Density

If you've ever been fooled by the old question, 'Which weighs more: a pound of feathers or a pound of lead?' then you wouldn't be alone. Although the feathers and the lead both weigh exactly the same (um, a pound), their density is wildly different, and we can sometimes mentally conflate weight and ...

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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