Compost C:N Ratio Calculator – Balance Browns and Greens (2026)
Calculate the carbon-to-nitrogen ratio of your compost pile and find out how to fix it if it is off.
Calculator Blog: Guides, Tips and How-To Articles
Practical guides and worked examples for our free online calculators, covering finance, health, maths, home projects and everyday conversions.
KDP Royalty Calculator – Kindle Ebook and Paperback Royalties (2026)
Calculate your Amazon KDP royalty for Kindle ebooks and paperbacks based on price, file size, and page count.
Print-on-Demand Profit Calculator – True Margin After All Fees (2026)
Calculate your real print-on-demand profit per sale after base cost, marketplace fees, processing, and ad spend.
Patreon Earnings Calculator – Estimate Your Real Net Payout (2026)
Calculate your true Patreon take-home pay after platform fees, payment processing, and failed payments.
Yarn Calculator – How Much Yarn Do I Need? (Knitting & Crochet)
Calculate exactly how much yarn you need for your knitting or crochet project based on gauge, stitch pattern, and project size.
Backyard Chicken Feed Calculator – Cost and Amount Needed (2026)
Estimate how much feed your backyard flock needs by age and stage, plus your monthly feed cost, with our free chicken feed calculator.
Soap Making Lye Calculator – NaOH and Water Amounts (2026)
Free lye calculator for cold process soap. Enter oil weights to get exact NaOH and water amounts based on SAP values and your chosen superfat.
Candle Making Cost Calculator – Price Your Candles Right (2026)
Calculate the true cost per candle including wax, fragrance, wick, container, labor, and get a suggested retail price with our free candle cost calculator.
GCF and LCM Calculator – Find Greatest Common Factor and Least Common Multiple
Free GCF and LCM calculator with step-by-step worked examples, prime factorization method, and a quick reference table.
Employee Turnover Rate Calculator – HR Formula and Benchmarks (2026)
Calculate your employee turnover rate and compare it to industry benchmarks with this free HR calculator and formula guide.