Guides
The detail behind each calculator — how the numbers are built, why the fees apply, and how to improve your result.
Shopify fees explained: how to calculate your real profit per sale
A plain-English breakdown of every Shopify fee — subscription, payment processing, and transaction fees — with worked examples and ways to pay less.
Read the guideAmazon FBA profit explained: how to find your real margin and ROI
Break down every Amazon FBA cost — referral fees, fulfillment fees, storage, and product cost — to find your true profit, margin, and ROI per unit.
Read the guideHow your mortgage payment is calculated (and how to lower it)
Understand every part of your monthly mortgage payment — principal, interest, taxes, insurance, and PMI — with the amortization formula and ways to pay less.
Read the guideHow long to pay off a loan — and how extra payments help
See how payoff time and total interest are calculated, why minimum payments trap you, and how much extra payments save on credit cards and loans.
Read the guideHow to set your freelance rate (so the math actually works)
Most freelancers undercharge. Learn how to turn your income goal, time off, expenses, and taxes into the hourly, day, and project rate you should charge.
Read the guideEtsy fees explained: how to work out your real profit per sale
A clear breakdown of every Etsy fee — listing, the 6.5% transaction fee, payment processing, and Offsite Ads — with a worked example and ways to keep more profit.
Read the guide