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📖 Blog · Long-form, math-honest guides

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Long-form articles about the things the site's tools calculate. No clickbait, no listicles, no "10 things your doctor won't tell you". Just the math, written out, with the assumptions named.

How mortgage payments really work — and what the bank's calculator doesn't show you

Finance & Money 7 min read

A practical, math-honest guide to how mortgage payments are calculated, what the standard formula misses, and how to think about overpayments, term changes, and total interest paid. Includes the one number the bank's calculator never shows you in the summary box.

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What BMI actually measures — and why your doctor still uses it

Health & Fitness 6 min read

A practical guide to what BMI is, what it isn't, why it survives as a population screening tool despite being useless for individuals, and what to use instead. Includes the three specific cases where BMI misleads, and the four better metrics in rough order of cost.

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Why compound interest is magic — and why the line goes up, not straight

Finance & Money 6 min read

A practical, honest guide to how compound growth works in real portfolios and real savings. Why the line is a curve, what the 8th duplicate of your money looks like, and when compound interest works against you. Includes the rule of 72 and the one counter-intuitive result that explains why the early saver always wins.

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