Guides
Plain-English explanations of the decisions behind the numbers, with worked examples and links to the calculators that do the math for you.
- Finance guideRenting vs Buying a Home: How to Compare the Real CostsCompare renting and buying on unrecoverable costs: interest, tax, upkeep, closing costs and lost investment growth, with a worked 7-year example.6 min read · November 8, 2026
- Finance guideAPR vs APY: What's the Difference?APR is the yearly rate on borrowing, often with fees and without compounding. APY includes compounding. See the formula and an APR to APY table.5 min read · November 8, 2026
- Finance guideDebt Avalanche vs Snowball: Which Pays Off Debt Faster?The avalanche method pays off debt with less interest; the snowball method gives quicker wins. See both compared month by month with three example debts.5 min read · November 8, 2026
- Finance guideHow to Build an Emergency Fund (and How Much You Need)How much to keep in an emergency fund, how to work out essential monthly expenses, how long saving takes, and where to keep the money.5 min read · November 8, 2026
- Finance guideReal Interest Rate: Why Inflation Matters for SavingsThe real interest rate is your return after inflation. See the exact formula, the quick approximation, worked examples and a table of real returns.5 min read · November 8, 2026
- Business guideHow to Price a Product: Cost-Plus Pricing ExplainedPrice a product with cost-plus pricing: add up your full unit cost, pick a target margin, turn it into a price, then check break-even and competitor prices.6 min read · November 8, 2026
- Business guideVAT Explained for Small Businesses and Online SellersWhat VAT is, how it differs from US sales tax, how to add and remove it correctly, and how VAT-inclusive pricing affects your margins as a small seller.6 min read · November 8, 2026
- Health guideBMI vs Body Fat Percentage: Which Is a Better Measure?BMI is quick but can't tell muscle from fat. See how BMI and body fat percentage differ, why two people with the same BMI can differ, and when to use each.6 min read · November 8, 2026
- Health guideCalorie Deficit Explained: Losing Fat Without Losing MuscleHow a calorie deficit works, how big it should be, why weight loss slows, and how protein and strength training help you keep muscle while losing fat.6 min read · November 8, 2026
- Fitness guideRunning Training Paces Explained: Easy, Tempo and IntervalWhat easy, tempo and interval runs are for, how to estimate each pace from a recent 5K, how they should feel, and a simple weekly plan for newer runners.5 min read · November 8, 2026