Loan Payoff Calculator for Weekly Payments

A weekly loan payoff calculator estimates how much each weekly payment must be, how many payments it may take, and the interest paid using your balance, APR, and payoff period. Enter the loan amount, annual interest rate, and number of years; the estimate converts the term to weekly payments and assumes a fixed rate and equal payments.

Formula

The calculator treats a year as 52 equal weekly periods. It converts the annual percentage rate (APR) to a weekly rate, calculates a level payment that amortizes the principal over the full number of weeks, rounds that payment to the nearest cent, and estimates total interest as the sum of those payments minus the original balance.

Weekly payment: Pmt = round[P × r ÷ (1 − (1 + r)⁻ⁿ), 2]

• P is the starting loan principal, in dollars.
• APR is the annual percentage rate entered as a percentage, such as 8 for 8%.
• r is the periodic weekly rate, calculated here as APR ÷ 5200. Dividing by 100 converts a percentage to a decimal, and dividing by 52 allocates it across 52 weeks.
• n is the number of weekly payments, calculated as loan term in years × 52.
• Pmt is the estimated weekly payment in dollars.

Total interest: Interest = Pmt × n − P. This uses the cent-rounded weekly payment, so small rounding differences can accumulate over many payments. The model assumes the same payment and rate each week and does not adjust the final payment to clear a residual balance exactly.

Worked Example

With the calculator’s default inputs—$20,000 principal, 8% APR, and a five-year term—the number of payments is 5 × 52 = 260. The weekly rate is 8 ÷ 5200 = 0.0015384615, or about 0.153846% per week.

1. Apply the level-payment formula: $20,000 × 0.0015384615 ÷ [1 − (1 + 0.0015384615)⁻²⁶⁰].
2. The unrounded result is about $92.05 per week; rounded to cents, the estimated payment is $92.05.
3. Multiply the rounded payment by the number of payments: $92.05 × 260 = $23,933.00 in estimated total payments.
4. Subtract principal: $23,933.00 − $20,000 = $3,933.00 estimated total interest.

Assumptions

• The interest rate stays fixed for the entire estimated term.
• Payments are equal, made once every week, and are applied at the end of each weekly period.
• Interest is compounded weekly at APR ÷ 52, a simplifying assumption for this calculator.
• Fees, taxes, insurance, escrow, late charges, and lender-specific payment allocation are not included.

When to Use a Weekly Payoff Estimate

Use a weekly estimate to understand the approximate cash amount associated with a chosen payoff term, or to compare the arithmetic of different terms using the same balance and APR. It can also provide a starting point when you are paid weekly and want to think about payments on a weekly schedule. It does not establish the amount your lender will accept or the payment schedule in your contract.

For a payoff date based on a payment amount you already make, this particular calculator is not enough: it asks for the term and solves for the payment. To estimate time to payoff from a fixed weekly payment, a calculator needs the payment amount as an input and must account for whether that amount covers interest. Check your statement or ask the lender for the current payoff balance, because it can differ from the original amount borrowed and a payoff quote may include accrued interest or other account-specific amounts.

How to Read the Results

The first result is the modeled weekly payment. The second is modeled interest over the complete term, not the total amount owed today. Adding principal and interest gives the estimated total paid under the assumptions. For the defaults, that total is $23,933.00. The figures are useful for understanding the formula, but the lender’s actual payment frequency, interest calculation, due dates, and final payment can change the result.

Weekly payments are not interchangeable with simply dividing a monthly installment by four. There are not exactly four weeks in every month, and a year has 52 weeks. A lender may instead set payments every 14 days, which is a different schedule from weekly: 26 two-week periods make 52 weeks, while weekly payments are made 52 times a year. Confirm whether “weekly” means every seven days and how the lender applies each payment.

Choosing Inputs and Common Problems

• Use the right balance. The starting principal is not necessarily the current payoff quote. Enter the balance appropriate to the question you are estimating.
• Enter APR as a percentage. Type 8 for 8%, not 0.08. The formula performs the percentage conversion.
• Match the rate to the loan terms. The calculator assumes the entered APR can be represented as a fixed annual rate divided into weekly periods. Variable rates or other interest conventions are not modelled.
• Check the payment frequency. A weekly schedule, biweekly schedule, and monthly schedule have different period counts and may have different payment amounts.
• Expect rounding. Payments are rounded to cents, so the last payment may need adjustment in an actual account. The displayed total interest is an estimate based on repeating the rounded payment for every period.

If the result seems inconsistent with a lender statement, check the principal, APR, remaining term, and payment timing first. Also check whether the quoted amount includes fees or whether payments are credited on receipt, on a due date, or under another schedule. This calculator cannot reproduce account-specific servicing details.

Frequently Asked Questions

How do I calculate a weekly loan payment?
Convert APR to a weekly rate by dividing the percentage rate by 5200, multiply the term in years by 52 for the number of payments, then use the level-payment formula shown above. Round the resulting payment to cents.

Is a weekly payment the same as a biweekly payment?
No. Weekly means one payment every seven days, typically 52 periods per year. Biweekly means one payment every 14 days, typically 26 periods per year. A calculator must use the schedule that applies to the loan.

Does paying weekly reduce total interest?
This calculator does not compare payment schedules. Any difference depends on how often the lender credits payments, the contract’s interest method, and whether the total amount paid per year changes. Ask the lender how it handles weekly or extra payments.

Can this calculator tell me when my current loan will be paid off?
No. It calculates a payment from a balance, APR, and selected term. Estimating payoff time from a payment amount requires a different calculation and accurate information about the lender’s balance and payment rules.

Why does my lender’s figure differ?
The lender may use a different balance, compounding or day-count convention, payment date, rounding method, or fees. The estimate also assumes a fixed rate and regular payments, so it will not match every account detail.

This result is an estimate for educational purposes; the lender’s disclosure gives the exact figures.

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in p | Loan amount | $ | 20000 | 1 | 100000000
in apr | Interest rate (APR) | % | 8 | 0.01 | 100
in yrs | Loan term | years | 5 | 0.0833 | 50
out pmt | Weekly payment | $ | round(p * (apr / 5200) / (1 - (1 + apr / 5200) ^ -(yrs * 52)), 2) | 2
out int | Total interest | $ | pmt * yrs * 52 - p | 2