Toolkit Shelf

Money Calculators

Loan Payoff Calculator

Use this loan payoff calculator to estimate how long a loan takes to pay off and how much interest you pay with regular and extra payments.

Reviewed May 25, 2026EstimateFormula shown

Live calculator

Loan payoff

Payoff time30 months

2.5 years at this payment.

Total interest$1,347.30

Estimated interest paid until payoff.

Total paid$13,347.30

Principal plus estimated interest.

Formula

Loan payoff formula

Monthly interest = balance x APR / 12; principal paid = payment - monthly interest; repeat until balance reaches zero

This calculator uses monthly compounding and assumes payments are made once per month.

How to use

Steps

  1. Enter the current loan balance.
  2. Enter the annual percentage rate.
  3. Enter the regular monthly payment.
  4. Add any extra monthly payment to see how payoff time changes.

Example

Sample calculation

Balance$12,000
APR8.5%
Payment$450/month
Payoff29 months

Calculator use

Best for

  • Quick payoff time from loan balance, apr and monthly payment.
  • Personal finance scenarios before changing a budget, loan, savings goal, or purchase plan.
  • Monthly cash flow, affordability, debt payoff, or future-value estimates.
  • Assumption checks before talking with a lender, tax preparer, employer, or financial professional.

Before relying on it

Check first

  • Entering loan balance, apr and monthly payment from different time periods or scenarios.
  • Mixing gross income, take-home income, one-time costs, and monthly costs in the same comparison.
  • Forgetting taxes, fees, insurance, irregular bills, or minimum payments when using an estimate.
  • Treating a planning estimate as a quote, tax filing result, approval decision, or guaranteed return.

Benchmarks

How to read the result

The calculator is a decision aid, not a fixed rule. Use the output to compare scenarios and document your assumptions.

Payment barely covers interestSlow payoff

Most of the payment goes to interest, so the balance drops slowly.

Extra paymentFaster payoff

Extra principal payments can reduce both payoff time and total interest.

High APRInterest sensitive

Higher interest rates make payment size and extra payments more important.

Calculator accuracy

Methodology and assumptions

The formula, inputs, example, and limitations are shown so the result is checkable, not just a number in a box.

Formula

Monthly interest = balance x APR / 12; principal paid = payment - monthly interest; repeat until balance reaches zero

Inputs used

Loan balance, APR, Monthly payment, Extra payment

Limitations

Results are estimates for quick planning and should be checked before important financial, legal, tax, health, or business decisions.

Last reviewed

May 25, 2026

Cite this page

Toolkit Shelf. Loan Payoff Calculator. Retrieved May 25, 2026, from https://toolkitshelf.com/tools/loan-payoff-calculator

FAQ

Common questions

How do extra payments affect loan payoff?

Extra payments usually reduce principal faster, which can shorten payoff time and lower total interest.

Why does the calculator say payment is too low?

That means the payment does not cover the first month's interest, so the balance would not go down.

Does this include fees?

No. It estimates principal and interest only unless fees are already included in the balance or payment.