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Estimate introductory and adjusted payments for an adjustable-rate mortgage scenario.
Adjustable-rate mortgage
An ARM calculator helps borrowers understand how an adjustable-rate mortgage may change after the introductory period ends. ARMs can start with a lower rate than a fixed-rate mortgage, but the future payment may rise if the adjusted rate is higher.
This tool estimates the monthly payment during the introductory period, the estimated payment after adjustment, the difference in payment, total payment, and total interest. It uses your initial rate for the intro period and an expected future rate for the remaining term.
Use this estimate with the Mortgage Calculator, Refinance Calculator, and Loan Comparison Calculator.
Calculator
The estimate updates instantly in your browser as you adjust the inputs.
This simplified ARM estimate does not include caps, margins, indexes, future rate changes, taxes, insurance, or lender fees.
Your input is processed in your browser. Dicno Labs does not upload or store the data you enter in this tool.
Guide
An adjustable-rate mortgage, or ARM, is a mortgage where the interest rate can change after an initial fixed period. A 5/1 ARM usually keeps the starting rate for five years and then adjusts once per year. A 7/1 ARM works similarly, but the introductory period lasts seven years.
The attraction of an ARM is often the initial rate. If that rate is lower than a fixed-rate option, the first payment may be lower. That can help borrowers who expect to move, refinance, or pay down the loan before the adjustment period matters. The tradeoff is uncertainty. If rates rise, the payment can increase after the intro period.
This calculator estimates the initial monthly payment using the starting rate and the adjusted payment using your expected future rate. It then estimates total payments by applying the initial payment during the intro period and the adjusted payment for the remaining months. It is a simplified planning model, not a lender schedule.
Pros of an ARM may include lower starting payment and flexibility for short time horizons. Cons include rate risk, payment shock, and complexity around indexes, margins, and caps. A borrower should understand the adjustment rules before choosing an ARM.
On a $350,000 loan, a 5.75% initial rate for five years may produce a lower first payment than a 7.25% future rate. If the loan adjusts higher after year five, the payment difference shows how much more monthly budget may be needed.
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References
An ARM is an adjustable-rate mortgage. It typically starts with a fixed introductory rate, then the rate can adjust later based on loan terms and market conditions.
A 5/1 ARM usually has a fixed rate for five years, then adjusts once per year after the introductory period.
A 7/1 ARM usually has a fixed rate for seven years, then adjusts once per year after that period.
Adjustment frequency is how often the interest rate may change after the introductory period, such as every 12 months.
No. It uses one expected future rate for a simplified estimate and does not model caps, indexes, margins, or lifetime limits.
An ARM may make sense for borrowers who expect to move, refinance, or pay off the loan before adjustments become important, but there is rate risk.
The main risk is that the payment can increase after the introductory period if the adjusted rate is higher.
No. It estimates introductory-period payments at the initial rate and remaining payments at the expected future rate.
Neither is automatically better. It depends on rate difference, risk tolerance, time horizon, refinance plans, and budget flexibility.
No. Your input is processed in your browser. Dicno Labs does not upload or store the data you enter in this tool.
HomeLoan Compass
Download HomeLoan Compass on Google Play for more complete mortgage planning tools, including affordability planning, loan comparison, amortization schedules, and future premium tools.