About 4FinanceCalculator
Free, transparent financial calculators that run entirely in your browser.
What 4FinanceCalculator is
4FinanceCalculator is a free collection of 12 financial calculators built to help you run the numbers before making a money decision — whether that is taking on a mortgage, comparing a loan, projecting investment growth, or planning for retirement. There is no sign-up, no paywall, and no app to install.
Your numbers stay private. Every calculation runs locally in your browser using JavaScript. The figures you enter are never uploaded to a server, so there is nothing for us to see or store.
The calculators
- Loans & debt: mortgage, loan, auto loan, amortization, payment, and interest.
- Investing & growth: compound interest, investment, and inflation.
- Long-term planning: retirement, income tax, and a general finance (time-value-of-money) solver.
Transparent by design
We show the formula behind each tool and update results the moment you type, so you can see exactly how a number is reached. Our income tax estimates use the official 2026 IRS federal brackets and standard deductions from Revenue Procedure 2025-32.
Educational, not advice
These tools are for education and planning. They produce estimates, not financial, legal, or tax advice. For decisions specific to your situation, please consult a qualified professional.
How it stays free
The site is supported by advertising through Google AdSense and by optional donations. That advertising uses cookies, which we explain in our Privacy Policy.
Contact
Questions or feedback? Email [email protected] or use our Contact page.