Match the amount, rate and time period
What could a loan payment look like?
Use these worked examples to understand the relationship between the amount borrowed, an entered interest rate and the repayment term. Then test your own assumptions in a calculator.
Compare loan amounts on the same basis
Hold the example rate at 12% and the term at 36 months. The payment rises in proportion to the principal when the other inputs stay the same.
| Amount borrowed | Monthly payment | Modeled total repaid | Modeled interest |
|---|---|---|---|
| $1,000.00 | $33.21 | $1,195.72 | $195.72 |
| $2,500.00 | $83.04 | $2,989.29 | $489.29 |
| $5,000.00 | $166.07 | $5,978.58 | $978.58 |
| $10,000.00 | $332.14 | $11,957.15 | $1,957.15 |
| $15,000.00 | $498.21 | $17,935.73 | $2,935.73 |
| $20,000.00 | $664.29 | $23,914.30 | $3,914.30 |
Totals use the unrounded mathematical payment, then round for display. Multiplying the displayed rounded installment can differ by a few cents.
A $10,000 example across four terms
Keep the same hypothetical 12% annual interest input. A longer term lowers this model’s installment while increasing its total interest. Check both columns before deciding whether a smaller payment is useful.
| Term | Monthly payment | Total interest | Total repaid |
|---|---|---|---|
| 12 months | $888.49 | $661.85 | $10,661.85 |
| 24 months | $470.73 | $1,297.63 | $11,297.63 |
| 36 months | $332.14 | $1,957.15 | $11,957.15 |
| 60 months | $222.44 | $3,346.67 | $13,346.67 |
Find the calculator for your question
Model a monthly installment
Enter principal, interest and term. Inspect the repayment schedule.
Check your household budget
Use take-home income, living expenses and a reserve to model a payment ceiling.
Compare actual written offers
Keep the amount and term consistent while reviewing quoted costs.
Allow for a deducted fee
Separate the note amount from cash received when a fee is withheld.
Review gross-income ratios
Compare debt payments with gross income separately from a take-home budget.
Plan existing debt repayment
Explore a repayment schedule using the balances and rates you enter.
What the formula includes
For principal P, monthly rate r and n payments, the modeled payment is P × r ÷ [1 − (1 + r)−n]. The monthly rate here is the entered annual interest rate divided by 12. When the rate is zero, the payment is P ÷ n. This simple fixed-rate model does not calculate a disclosure APR, add origination fees, predict approval or account for irregular payment dates.
Keep the numbers in context
- Ask whether a quoted payment includes all required products or charges.
- Compare the APR and finance-charge disclosures alongside the note rate; the terms describe different measures.
- Check the cash you actually receive, the final installment and any early-repayment terms.
- Stress-test the payment against essential expenses and a reserve, rather than treating a lender limit as a spending target.
Use the quote comparison worksheet, fee and net-proceeds worksheet, application worksheet and DTI input worksheet to organize questions. For eligibility, timing and verification, browse the borrowing guides.
Source and scope
CFPB explanation of personal installment loans. The calculations above are original hypothetical illustrations prepared November 7, 2026. Current offers and your contract require separate verification.