onlinecalculator.me

Free online loan calculator

A loan is borrowed money you pay back with interest. This calculator shows the monthly payment and total interest for any fixed-rate loan — student, personal, anything.

Monthly payment
$—
Total interest
$—
Total paid
$—
About this calculator

How to use

  1. Enter the loan amount (principal), the annual interest rate (APR), and the term in years.
  2. Optionally add an extra monthly payment to see how it shortens the loan and reduces interest.
  3. Press “Show schedule” to see the full month-by-month amortization table.
  4. Press “Share with my numbers” to save or send your scenario.

The formula

      P · r · (1 + r)^n
M  =  ─────────────────
        (1 + r)^n − 1
  • P — loan principal
  • r — monthly rate = annual APR / 12 / 100
  • n — total payments = years × 12

Each month: Interest = balance × r, Principal = M − interest, New balance = balance − principal.

Worked example

$20,000 personal loan at 7% APR for 5 years:

  • r = 0.07 / 12 ≈ 0.005833
  • n = 60
  • M ≈ $396.02/month
  • Total paid: ≈ $23,761 — so $3,761 in interest

Adding $100/month extra cuts the term to about 50 months and saves roughly $590 in interest.

Notes

  • APR is the yearly rate; this calculator divides it by 12 for monthly compounding, which is standard for US installment loans.
  • Some loans compound daily. If yours does, your actual payments may differ slightly.
  • This tool is for planning — compare against the official Truth-in-Lending disclosure for your actual loan.

Frequently asked

How is the monthly loan payment calculated?
The standard annuity formula: M = P × r(1+r)^n / ((1+r)^n − 1), where P is the principal, r is the monthly rate (annual APR ÷ 12), and n is the number of monthly payments. At 0% interest, the payment is simply P / n.
What effect does an extra monthly payment have?
Extra payments reduce the principal faster, which cuts total interest and shortens the loan term. Every dollar of extra principal saves you roughly that dollar's worth of future interest. The calculator shows the revised payoff date and total savings.
How does this differ from the mortgage calculator?
The math is identical. The loan calculator is simpler — just principal, rate, term, and extra payment. The mortgage calculator adds property tax, insurance, HOA, and PMI in extended mode.
Can I calculate a student loan payoff?
Yes. Enter the current balance as the principal, your interest rate (APR), and the remaining term in years. The calculator gives the standard payment and shows how extra payments accelerate payoff.
How do I share a loan scenario?
Press "Share with my numbers" — your inputs are encoded in the URL and copied to your clipboard.