Category
Calculators & Finance
Clear, worked-example guides to the calculations people actually need: percentages, loan repayments, interest, tax, discounts, tips and BMI. Every guide explains the formula in plain English and links to a free calculator that does the maths for you.
Calculators & Finance
Every Free Calculator on TontonTools
The complete list of TontonTools' free calculators — 28 tools, no signup, in your browser.
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Calculators & Finance
Every Free Unit Converter on TontonTools
The complete list of TontonTools' free unit converters — 18 tools, no signup, in your browser.
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Calculators & Finance
How to Calculate a Percentage (The 3 Methods You Actually Need)
Percentages trip up more people than they admit. Here are the three calculations you actually need, with plain worked examples for each.
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Calculators & Finance
How Loan EMI Is Calculated (With Worked Examples)
Wondering how your monthly loan payment is worked out? Here is the EMI formula explained simply, with a real example and a free calculator.
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Calculators & Finance
What Is a Good BMI? How to Read and Use Your Number
BMI is a quick health screening number — but only if you know how to read it. Here is what the ranges mean and where BMI falls short.
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Calculators & Finance
How to Calculate Discount and Final Sale Price
See exactly how much you save in a sale. Here is how to calculate a percentage discount and the final price, with quick examples and shortcuts.
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Calculators & Finance
Markup vs Margin: What's the Difference (and How to Calculate Each)
Markup and margin sound the same but mean very different things — and confusing them costs businesses money. Here is how to calculate both.
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Calculators & Finance
Compound Interest Explained: How Your Money Grows
Compound interest is the most powerful force in personal finance. Here is how it works, why time matters so much, and how to calculate it.
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Calculators & Finance
How to Calculate Sales Tax, VAT and GST
Adding tax to a price is simple once you know the steps. Here is how to calculate sales tax, VAT and GST — and how to work backwards from a total.
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