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Guides & Explainers
Plain-English walkthroughs of the math behind every CalcPond tool. No jargon, no filler — just clear explanations you can actually follow, with worked examples throughout. Each guide links to the calculator it explains.
Age & dates
- How to Calculate Your Exact Age in Years, Months and Days
- How to Count Business Days Between Two Dates
- Leap Years Explained: Why 1900 Wasn't One
Percentages & conversions
- How to Calculate Percentage Increase and Decrease
- Percentage vs. Percentage Point: The Difference That Costs People Money
- The Complete Guide to Metric and Imperial Conversions
Money & loans
- How Loan Amortization Actually Works
- Fixed vs. Variable Rate Loans: A Plain-English Comparison
- How Much House Can You Actually Afford?
- Compound Interest: The Math Behind the Cliché