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Financial

Auto Loan Amortization Calculator

Generate an amortization schedule for your car loan: each month's interest, principal, and remaining balance. Model extra principal payments and see total interest paid.

What this calculator is for

An auto loan amortization schedule lists each month’s interest, principal, and remaining balance — the table banks generate but rarely print for car loans. Seeing month-one interest vs principal explains why early payoff saves so much and why 72-month notes feel “endless.”

Useful for buyers negotiating term, for anyone adding $50–$200 extra principal, and for tutors explaining how APR works on real paper. The built-in table shows the first year plus summary totals; the math section lets you verify any row by hand.

A good outcome: you know total interest over the life of the loan and can point to the month when principal finally beats interest — often later than people expect on long terms at moderate APR.

Calculator

How to use this calculator

  1. Enter loan amount, APR, and term in months — payment is calculated automatically.
  2. Review month 1 interest vs. principal and the 12-month schedule below the results.
  3. Add optional extra principal per month to see interest saved and a shorter payoff.

APR is annual; the tool converts to monthly rate (APR ÷ 12 ÷ 100). Biweekly loans use a different period count — use the biweekly calculator for that pay schedule.

Extra principal in the schedule assumes it is applied the same month you enter — real lenders may apply on the next cycle.

Round-off pennies: last payment may differ by a few cents from the lender’s system.

The math: do it without a calculator

Payment = standard amortization formula (same as auto loan calculator)

Each month: Interest = prior balance × monthly rate

Principal = Payment − Interest (+ extra if any)

Month k interest = balancek−1 × r. Principal = payment − interest (+ extra). New balance = old − principal.

Sum of payments = n × payment (fixed-rate level pay). Total interest = sum of payments − original principal.

Real-world examples

$28,000 loan at 6.5% / 60 months

Payment lands near $548. Month one interest is roughly $152 and principal about $396 — by month 48, principal share is much larger. Total interest over five years is about $4,900 if you never add extra.

Troubleshooting & fine-tuning your setup

Amortization Table Does Not Match My Statement

Statements reflect actual payment posting dates, fees, and skipped payments. This schedule assumes fixed payment and on-time pay every month.

If balance on month 12 is off by more than a few dollars, check APR entry (note rate vs APY) and whether your loan is simple interest daily accrual with irregular payments.

Frequently asked questions

Amortization Schedule FAQs

Why is so much of my early payment interest?

Interest is charged on remaining balance. Early in the loan the balance is high, so the interest portion is large — normal amortization behavior.

How much does $50 extra principal save?

Depends on APR and remaining term — use the extra payment field here; savings grow with higher APR and longer remaining term.

Is amortization the same for biweekly loans?

Biweekly schedules use 26 periods per year — use the biweekly calculator for that pay pattern.

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