What we publish

The library covers the searches people actually run: secondary-market payouts (eBay, Poshmark, Fashionphile, The RealReal, StubHub, Ticketmaster Resale), mortgage and refinance payments, loan amortization, compound interest, tips, BMI, a Navy-method body-fat estimate, TDEE, paint and flooring takeoffs, concrete volume, tile counts, unit converters, and percentage math.

How the numbers are produced

Every tool is static HTML, CSS, and JavaScript. Formulas are documented on each page. Finance tools use standard amortization. Health tools use published screening formulas (WHO BMI, Mifflin–St Jeor, U.S. Navy circumference) and are labeled as estimates. Converters use SI and customary conversion factors.

Privacy

Inputs never leave your browser for the calculation itself. We do not operate a results database. If display advertising is enabled later, third-party ad networks may set cookies — see the Privacy Policy.

Accuracy

We test the core formulas against known examples, but lenders, clinicians, and contractors use their own rounding, fees, and product rules. Treat every result as a planning estimate.

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