Loan & Compound Interest Calculator
✓ Link copiedPlan your borrowing and saving in one place, entirely in your browser. The loan mode uses the standard amortizing formula (等额本息) to turn a loan amount, annual interest rate, and term into a constant monthly payment, the total interest you will pay, and the total of all payments. The compound-interest mode projects how a starting balance grows over time, with your choice of compounding frequency — annual, monthly, daily, and more — and optional recurring contributions, showing the future value, everything you put in, and the interest earned on top. Every calculation runs locally with no sign-up and nothing sent to a server. Use it to compare mortgage or car-loan scenarios, sanity-check a lender's quote, or see how regular saving compounds. Free, fast, and private.
Monthly payment
1,199.10
- Total interest
- 231,676.38
- Total of payments
- 431,676.38
How to use
Pick a mode at the top. For a loan, enter the amount borrowed, the annual interest rate, and the term in years — the monthly payment, total interest, and total of payments update instantly. For compound interest, enter your starting balance, annual rate, number of years, any recurring contribution, and how often interest compounds to see the projected future value. Use the Copy button to grab the results.
Frequently asked questions
- How is the monthly loan payment calculated?
- The loan mode assumes a fixed-rate, fully-amortizing loan (等额本息) — the same payment every month until the balance reaches zero. It applies the standard annuity formula M = P · r / (1 − (1 + r)⁻ⁿ), where P is the amount borrowed, r is the monthly rate (annual rate ÷ 12), and n is the number of months. A 0% rate simply splits the principal evenly across the term.
- How does the compound-interest projection work?
- Future value is computed as P · (1 + i)ⁿ for the starting balance, where i is the periodic rate (annual rate ÷ compounding frequency) and n is the number of periods. Recurring contributions are added as an ordinary annuity — deposited at the end of each period — so a higher compounding frequency or a larger contribution produces a higher ending balance for the same nominal rate.
- Are these numbers financial advice?
- No. The calculator is a mathematical tool that ignores fees, taxes, insurance, variable rates, extra payments, and inflation, and assumes a constant rate throughout. Real loans and investments differ. Treat the results as estimates for comparison and planning, and confirm exact figures with your lender or a qualified financial professional.