Prime Calc Tools was built on a simple belief: the financial tools used by professionals should be accessible to everyone — not locked behind expensive software or paywalls.
We build accurate, jargon-free financial calculators that help individuals, small business owners, real estate investors, and finance professionals make better decisions with their money.
Whether you're calculating the IRR on a private equity deal, stress-testing an LBO model, planning your retirement with the 4% rule, or just figuring out how much house you can afford — our tools are designed to give you the same depth of analysis that advisors and analysts use every day.
Every formula is vetted against industry standards. We'd rather build fewer calculators than ship inaccurate ones.
All 35+ calculators are completely free with no account needed. Your calculations stay on your device.
From basic compound interest to LBO modeling and fund waterfall distributions — we cover the full spectrum of financial analysis.
Clear explanations, plain-language results, and educational context so anyone can understand their numbers — not just finance pros.
We regularly update our calculators based on user feedback, tax law changes, and new financial methodologies.
Every calculator includes context, benchmarks, and explanations so you leave with a better understanding — not just a number.
Compound interest, net worth, HYSA, debt payoff, emergency fund, tax withholding
401(k), Roth IRA, FIRE planning, portfolio rebalancing, dollar-cost averaging, IRR & MOIC
Mortgage payments, home affordability, refinance break-even, rent vs. buy, auto, student loans
EBITDA, business valuation, DSCR, cap rate, LBO modeling, M&A deal analysis, fund waterfall
We're always looking to improve. If there's a calculator you'd like to see, or something we can do better, we'd love to hear from you.