About CalculateMyStuff.com

CalculateMyStuff.com was built with a simple mission: give everyone free, instant access to the calculators they need to make smarter decisions.

Whether you're a marketer measuring campaign ROI, a freelancer setting rates, a homeowner estimating renovation costs, or a startup founder modeling runway — the right calculation at the right time can save hours of guesswork and thousands of dollars in mistakes.

What We Cover

Our growing library of calculators spans multiple categories:

• Marketing — ROAS, CTR, CPC, break-even analysis, customer acquisition cost, and more.
• Marketplace Fees — Depop, Mercari, Poshmark, StockX, Fiverr, StubHub, and Ticketmaster fee calculators.
• Freelance & Consulting — Billable hours, hourly rate, and income projection tools.
• Accounting & Finance — Profit margins, gross profit, and financial analysis.
• Home Costs — Roofing, mortgage, renovation, and utility estimators.
• HR & Health — Salary calculators, BMI, fasting schedules, and benefits cost tools.
• Real Estate & Startup — Rental yield, burn rate, runway, and valuation calculators.

Built on Verified Formulas

All calculators are built using verified formulas and industry-standard methodologies. We research each tool's underlying math, cross-reference with official sources and industry publications, and clearly explain the formulas so you understand exactly how your results are calculated.

Always Free, No Signup

Every calculator on CalculateMyStuff.com is completely free to use. There's no account required, no email gate, and no limit on how many calculations you can run. Your data stays in your browser — we don't store your inputs or results on our servers.

Have a Suggestion?

We're always adding new tools. If there's a calculator you'd like to see, or if you spot an issue with an existing one, please get in touch. We'd love to hear from you.