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Payment Calculator

Find your monthly payment for any loan given principal, rate, and term.

⚡ Instant results🔒 Private — runs locally🆓 Free forever🚫 No signup

Payment Calculator

Find your monthly payment for any loan given principal, rate, and term.

⚡ Instant🔒 Private🆓 Free🚫 No signupFinancially accurate
$
%
years
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Loan Payment Formula

M = P × [r(1+r)ⁿ] ÷ [(1+r)ⁿ – 1]
M = Monthly payment
P = Principal (loan amount)
r = Monthly interest rate (annual rate ÷ 12)
n = Total number of payments (years × 12)

ℹ️ Total interest paid = (M × n) – P

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Disclaimer

Results provided by this calculator are for informational and educational purposes only. They are based on the values you enter and standard formulas, and should not be considered financial, medical, legal, or professional advice. Always consult a qualified professional before making important decisions based on these results. Roughtools makes no warranties regarding the accuracy or completeness of these calculations for your specific situation.

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Frequently Asked Questions

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Pro Tips

1

Even a 0.5% lower interest rate saves thousands over the life of a loan. Shop at least 3 lenders and get pre-approval before committing — lenders compete on rate when they know you have options.

2

Making one extra payment per year directly toward principal can shorten a 30-year mortgage by 4–6 years and save over $30,000 in interest on a typical home loan.

3

Your Annual Percentage Rate (APR) includes fees the interest rate does not — always compare APR, not just rate, when evaluating lender offers.

4

Bi-weekly payments (half the monthly amount every 2 weeks) result in 26 half-payments per year — equivalent to 13 full monthly payments instead of 12, accelerating payoff.

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When to Use This Calculator

🚗Auto loan comparison

Compare dealer financing vs. bank pre-approval to find the lowest monthly payment and total cost before you sign.

🎓Student loan planning

Estimate monthly payments before taking out student loans to ensure they fit within your future income budget.

💼Business loan analysis

Calculate the cost of a business loan before applying — know your break-even point before borrowing.

🏦Comparing loan offers

Enter identical principal and term with different rates to instantly compare the true cost of competing offers.

📊Debt consolidation planning

See if consolidating multiple debts into a single lower-rate loan reduces your total monthly payment and interest.

About the Payment Calculator

This payment calculator finds your fixed monthly payment for any loan using the standard amortization formula. Enter the loan amount, annual interest rate, and repayment term to instantly see your monthly payment and total interest paid. Ideal for personal loans, car loans, and business financing — no signup needed.

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How to Use the Payment Calculator

  1. 1

    Enter the total loan amount (principal) in dollars.

  2. 2

    Enter the annual interest rate as a percentage.

  3. 3

    Enter the loan term in years or months.

  4. 4

    Your monthly payment and total cost appear automatically.

  5. 5

    Adjust any input to compare different loan scenarios side by side.

View all →

Your input is processed locally in your browser and is never stored, transmitted, or shared with any server. See our Privacy Policy.

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