About the Repayment Calculator

Whether you are paying back a friend, a personal loan, or analyzing a generic financing offer, having a clear repayment timeline is essential. The Repayment Calculator is a versatile tool designed to answer one specific question:"If I pay $X per month, how long will it take to clear this loan?"

Unlike standard amortization calculators that ask for a loan term (e.g., 5 years) and calculate the payment, this tool works in reverse. You set the payment you can afford, and it tells you the timeline. This is perfect for flexible debt arrangements or aggressive repayment planning.

How to Use This Calculator

Enter the following details:

• Loan Amount: The total principal you borrowed or currently owe.
• Interest Rate (%): The annual interest rate. If you are borrowing from a friend or family member at 0% interest, simply enter 0.
• Monthly Payment: The fixed amount you plan to pay every month.

How the Calculation Works

The calculator iteratively applies your payment to the outstanding balance.
Formula Step 1: Calculate monthly interest cost (Result = Balance × Rate / 12).
Formula Step 2: Subtract interest from your monthly payment to find the principal payment.
Formula Step 3: Deduct principal payment from the balance.
This loop continues until the balance is zero.

Important Note: If your Monthly Payment input is less than the monthly interest accrued, the loan can never be paid off. The calculator will detect this "mathematically impossible" scenario and alert you immediately.

Understanding Your Results

The primary output is the **Repayment Period**—the exact duration in years and months until the loan is settled.

Total Paid: This figure helps you understand the efficiency of your payment. If you borrow $10,000 and the "Total Paid" is $15,000, you are paying a 50% premium for the liquidity. Increasing your monthly payment by even a small margin can drastically reduce this gap.

Practical Example

Loan: $10,000 personal loan.
Rate: 10%.
Payment: $200/month.

Result: It will take roughly 5 years and 4 months to repay. You will pay roughly $2,700 in interest.
If you increase the payment to $300/month, the timeline drops to 3 years and 2 months, and interest drops to roughly $1,600.

When and Why This Calculator Is Useful

Use this calculator when:

• Setting terms for private loans: If you are lending money to family, use this to agree on a fair payment schedule.
• Aggressive debt payoff: See how fast you can kill a specific loan by throwing "extra" money at it.
• Scenario Planning: Quickly toggle the "Monthly Payment" up and down to see how sensitive the timeline is to your budget changes.