Loan Calculator
Estimate payments, total interest, payoff date, and total cost for personal loans, business loans, and other fixed-rate loans.
Monthly payment
$420
Number of payments60
Total interest$5,202
Total paid$25,202
Formula
M = P × [r(1 + r)ⁿ] ÷ [(1 + r)ⁿ − 1]
P is the loan amount, r is the monthly rate, and n is the total number of monthly payments.
Methodology & sources
Every formula on this page is verified against the authoritative publications listed below. Assumptions describe the boundaries of the estimate.
Formulas
- M = P × [r(1+r)^n] ÷ [(1+r)^n − 1] where r = APR/12, n = months
- Total interest = M × n − P
Assumptions
- Fixed APR for the entire term.
- Equal monthly installments; no origination fees or prepayment penalty.
- APR is treated as the nominal annual rate compounded monthly.
Citations
- [1]Truth in Lending Act (Regulation Z) — APR and payment disclosure — Consumer Financial Protection Bureau (CFPB).Verified 2026-07-22.
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This calculator provides estimates only. Results depend on the values entered and may not account for every individual situation. This site does not provide financial, tax, legal, investment, medical, or academic advice.