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Education & StudentsPopular

Loan Repayment Estimator

Estimate monthly payments, total interest, and payoff timeline for student loans with optional extra payment modeling.

The total principal balance of your student loan.

Additional amount paid monthly beyond the minimum to reduce total interest.

Your Results

$

Enter your loan details and click calculate.

What This Calculator Does

This student loan repayment calculator estimates monthly payments, total interest paid, and payoff timeline for student loans. It uses the standard amortization formula and supports extra monthly payments so you can see how paying more reduces your total cost and payoff time. The yearly breakdown shows how your payments shift from interest-heavy to principal-heavy over time.

The Formula

Monthly Payment = P x [r(1+r)^n] / [(1+r)^n - 1]

P is the loan principal, r is the monthly interest rate (annual rate divided by 12), and n is the total number of payments (years multiplied by 12). Extra payments reduce the principal faster, lowering total interest and shortening the payoff period.

Step-by-Step Example

1

Enter loan balance

Input your total student loan balance. Example: $35,000.

2

Enter interest rate

The annual interest rate on your loan. Federal student loan rates for 2026 are approximately 5.5% for undergraduate and 7.0% for graduate loans.

3

Enter loan term

Standard repayment is 10 years. Extended plans go up to 25 years.

4

Add extra payments

Optional: adding $100/month extra to a $35,000 loan at 5.5% saves approximately $3,400 in interest and pays off 2 years early.

Real-World Use Cases

Post-Graduation Planning

Understand your monthly obligation before your grace period ends and plan your budget accordingly.

Refinancing Analysis

Compare your current payment with a refinanced loan at a lower rate to see potential savings.

Extra Payment Strategy

See exactly how much you save by making extra monthly payments or lump sum payments.

Common Mistakes to Avoid

  • Not accounting for the grace period. Federal student loans typically have a 6-month grace period after graduation before payments begin.

  • Ignoring income-driven repayment options that may lower monthly payments based on your income and family size.

  • Refinancing federal loans to private loans without considering the loss of federal benefits like income-driven repayment and loan forgiveness.

  • Only making minimum payments when you can afford more. Even small extra payments significantly reduce total interest.

Frequently Asked Questions

Accuracy and Disclaimer

This calculator provides estimates based on the standard amortization formula. Actual student loan terms may include variable rates, income-driven repayment options, deferment, forbearance, and forgiveness programs not modeled here. Contact your loan servicer for exact figures.