The loan calculator accurately calculates your monthly payment based on loan amount, interest rate and term. It also shows the full amortization schedule so you can see exactly how each payment is split between interest and principal.
Enter the loan amount, annual interest rate and term in years. The calculator instantly computes the monthly repayment.
Over the life of a loan, early payments are mostly interest. As the principal reduces, the interest portion decreases and more goes toward repayment.
Use this calculator before accepting any loan offer — not after. Comparing the total interest cost across two loan options at the same rate but different terms reveals the true price of a lower monthly payment. It is also useful when deciding whether to pay off a loan early: run the current balance as a new loan against the remaining term to see what interest you would save by overpaying.
Many borrowers compare loan offers by monthly payment alone — this is misleading. A longer term always produces a lower monthly payment but a higher total cost. A 5-year loan at 6% on £10,000 costs £1,073 in total interest; the same loan over 7 years costs £1,519 — a 42% increase in interest for a marginally lower monthly figure. A second common error is ignoring arrangement fees, which lenders quote separately from the interest rate but which add directly to the cost of the loan.
A buyer finances a £18,000 car at 5.9% APR over 48 months — monthly payments of £421, total interest £2,224. Running the same amount over 60 months drops payments to £347 but raises total interest to £2,820. The £74/month saving costs an extra £596 over the life of the loan. Making this comparison takes about 30 seconds with this calculator — and it is the kind of decision most people make without running the numbers.
Monthly Payment (Amortization) Formula
M = P × [r(1+r)^n] / [(1+r)^n − 1]
Where M = monthly payment, P = principal loan amount, r = monthly interest rate (annual rate ÷ 12), n = total number of payments (years × 12).
You take a $200,000 car loan at 5% annual interest for 5 years. What is your monthly payment?
Result: Monthly payment = $3,774.25 — total interest paid = $26,455
Enter the loan amount (e.g. $300,000), interest rate (e.g. 4%) and term (e.g. 30 years). The calculator uses the standard amortization formula.
A breakdown of each monthly payment split into interest and principal repayment, showing how the balance decreases over time.
A 1% increase in interest rate on a $300,000 30-year mortgage adds roughly
Fixed-rate loans keep the same interest rate for the full term. Variable rates can change with market conditions, affecting your monthly payment.
CalcPlanet – Free Online Calculators
725+ free calculators and 108 tools for math, money, health, and everyday life. Instant results, verified formulas, no sign-up.
By CalcPlanet Editorial · Reviewed against our Editorial Standards and Formula Sources.
CalcPlanet calculators are free, privacy-first, and formula-reviewed.
Editorial Standards · Formula Sources · Privacy · Terms · Contact
