How it works
Calculate equal monthly principal-and-interest payments for a fixed-rate loan. Fees and insurance are excluded.
Inputs and units
| Input | Example value | What to enter |
|---|---|---|
| Loan principal | 20,000 | Enter a numeric value. Must be greater than zero. |
| Annual interest rate | 10 % | Enter the percentage as a number: for 15%, enter 15. Use the annual rate. Use a non-negative value. Allowed range: 0–100. |
| Monthly payments | 36 | Enter a numeric value. Use a whole number. Must be greater than zero. Allowed range: 1–1,200. |
Worked example
Show example inputs and results
This example is generated by the same calculation engine using the starting values in the form. Your own inputs produce your own result.
- Loan principal
- 20,000
- Annual interest rate
- 10 %
- Monthly payments
- 36
Complete example results
- Monthly payment
- 645.34374388
- Total interest
- 3,232.37477956
- Total paid
- 23,232.37477956
Reading the result
Match the rate period to the payment period. Fees and taxes absent from the inputs are not added automatically; compare totals with the same cost coverage.
Questions and answers
Can I use the example values for my own calculation?
The example values illustrate the calculation. Replace every input with your own information, especially dates, rates and the selected operation.
Why are some results rounded?
Results display up to 8 decimal places. Calculations use the unrounded values; very small values use scientific notation. JavaScript floating-point arithmetic can introduce tiny rounding differences.
Are my inputs sent to a server?
The calculator processes inputs in your browser. Its code does not send your values to a server.