Loan-payment guide: fixed monthly repayment estimate

When this tool helps

This is a planning calculation for a fixed-rate loan with monthly payments. The annual percentage rate entered is divided by 12 to form the monthly rate used in the formula. Principal, interest and term should therefore match the same simple repayment model.

Enter the loan amount, annual interest rate and a whole number of months. Compare the result with a lender’s actual repayment schedule rather than assuming it is a quote. Charges, interest conventions and contract terms can materially change a real agreement.

What to enter

These are the candidate Android fields, not a form on this website. Editable fields in the app start empty; modes and units are selected separately.

Loan amount: The principal being repaid, not the total of all instalments.
Annual interest rate (%): A non-negative annual rate supplied by you.
Number of months: Whole months from 1 to 1,200.

Worked example · not prefilled app data

Try this example after the update is available

The values below explain the calculation. They are not a quote, a live measurement or an automatic answer for your situation.

Loan amount: 100000
Annual rate (%): 12
Number of months: 12

Checked example result8,884.88 / month

For 100,000.00 over 12 months at an entered annual rate of 12%, the model uses a 1% monthly rate and gives a displayed monthly estimate of 8,884.88.

Formula and assumptions

Payment = P × r ÷ [1 − (1 + r)^(−n)], where r = annual percentage ÷ 1,200 and n = months

With a zero rate, payment is principal divided by the number of months. Rates above 1,000% and terms above 1,200 months are rejected.
The model assumes constant monthly payments and excludes fees, taxes, introductory rates, insurance, extra repayments and payment-date differences.

A common mistake to avoid

Do not enter an already monthly percentage in the annual-rate field. Displayed payment rounding can also differ from a lender’s final adjusted instalment.

Find this tool in the Android update

When you have the redesigned Android update, open Tools and search for Loan payment, or find it under Money.
Open the tool, choose the mode or units relevant to your task, then enter your own values.
Review the result and explanation. Use Calculate & save only if you want the calculation kept in local History; Copy result does not send it to our server.

This guide is an educational preview of the update in testing, not an announcement that Google Play has approved or published it. Calculations are in the native app; no web calculator or download is offered on this page.

Questions about Loan payment

Can I calculate an interest-free loan?

Yes. Enter an annual rate of 0; the model divides the principal across the selected months.

Is this a lender offer or affordability decision?

No. It is a formula-based estimate, not a quote, approval, credit assessment or financial recommendation.