Repayment Calculator
Adjust the inputs below. Results update as you type.
How it works
Monthly payment = P × r(1+r)^n / ((1+r)^n − 1). Each payment covers interest first; the remainder reduces principal. Paying even $50 extra per month on a $20,000 loan at 6% saves ~$500 in interest and pays off 10 months early. For student loans, income-driven repayment caps payments at 5–20% of discretionary income—separate calculators apply.
Input guidance
- Use realistic rates from lender or provider quotes instead of headline averages.
- Model conservative, baseline, and optimistic scenarios before deciding.
- Include recurring real-world costs (fees, taxes, insurance, maintenance) where relevant.
The formula
Repayment uses the standard amortization formula M = P · r · (1+r)^n / ((1+r)^n − 1) to find the regular payment, or solves for the term given a chosen payment.
Worked example
A $30,000 loan at 8% repaid over 7 years requires about $468/month; shortening to 5 years raises the payment to about $608 but cuts total interest substantially.
More examples to test
- Conservative case: use a higher interest rate and lower growth assumptions to stress-test affordability.
- Optimistic case: use a lower rate with stable income assumptions to compare upside potential.
How to interpret results
Treat this as a planning model, not a final approval tool. Compare at least two scenarios and focus on total-cost and cash-flow trade-offs.
When this can be inaccurate
Results can diverge due to fees, changing rates, tax rules, lender policies, and behavior changes that simplified models cannot fully capture.
Change history
- July 2026: Quality-reviewed for publication with formula checks and explanatory copy updates.
Site-wide corrections also appear on the corrections log.
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Frequently asked questions
What affects my repayment amount?+
The amount borrowed, the interest rate, and the term. A longer term lowers each payment but increases the total interest you pay.
Can I repay early?+
Usually yes, and it saves interest. Check whether your agreement has any early-repayment charges before making large extra payments.
Fixed or variable rate?+
Fixed keeps payments predictable; variable can start lower but rises and falls with market rates, changing your repayment over time.
How should I use this result?+
Treat it as a planning estimate. Compare at least two realistic scenarios, then confirm with statements, quotes, or a qualified professional before acting.
How often should I refresh assumptions?+
Refresh whenever rates, income, costs, or policy limits change materially, and before making irreversible commitments.