Guides hub · Updated August 9, 2026
Guides that answer the next question
Direct answer: start here when you need a clear recommendation, comparison, or citeable number — then jump into the matching free calculator. Each guide shows an update date, worked example, and honest limits.
12 pages
Comparisons, how-tos, use cases, research
Citeable format
Direct answer → example → limits → FAQ
Free tools
Every guide links to a live calculator
- How-toHow to calculate USPS postageBillable weight (DIM ÷ 166), Priority vs Ground Advantage examples, Flat Rate boxes, and a free postage calculator.
- How-toHow to calculate capital gains tax on a property saleSale − basis − expenses, Section 121 ($250k / $500k), home vs rental examples, and a free calculator.
- How-toWhat is the Wells score for DVT?Nine criteria (−2 to +9), low/moderate/high bands, D-dimer pathway teaching, and a free Wells DVT calculator.
- How-toHow do you calculate the CHA₂DS₂-VASc score?Acronym points, Friberg annual stroke risk %, anticoagulation teaching thresholds, and a free calculator.
- Use caseHow much is scrap metal worth?Direct answer for copper, aluminum, brass, and steel by the pound, with a worked example and calculator.
- Use caseHow much will my TSP grow?Citeable Thrift Savings Plan projections with contributions, match, and compound growth — plus a free calculator.
- Use caseHow much weight will I lose on a water fast?3-, 5-, and 7-day citeable estimates (fat vs water), safety limits, and a free calculator.
- ComparisonFree online calculator sites comparedHonest comparison of The Calcs vs Calculator.net, Omni Calculator, and Desmos — best for, limits, and when to use each.
- How-toHow do I round to the nearest tenth?The hundredths-digit rule with homework answers: 36.89753 → 36.9, 8.329 → 8.3, and more.
- How-toHow do I convert feet and inches?12 inches = 1 foot. Convert, add, and subtract ft/in with worked examples and a free calculator.
- Use caseHow many acres is my lot?Acres = square feet ÷ 43,560. Common lot sizes with citeable examples and a free land calculator.
- ResearchCalculator search demand benchmarks (2026)Citeable numbers from our Google Search Console export — top impression topics and CTR gaps.
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