PMI Calculator
Monthly mortgage insurance.
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Real Estate
ARM Calculator
See your initial payment and the payment after the rate resets.
Initial payment
—
During the fixed period.
| Payment after reset | — |
|---|---|
| Balance at reset | — |
| Rate change | — |
| — |
Show our math
Enter your figures above to see the step-by-step working.
Educational estimate — not a loan offerEverything computed client-side — nothing leaves this page
How the ARM Calculator Works
An adjustable-rate mortgage (ARM) has a fixed rate for an intro period — the 5 in a 5/1 ARM means five years — then the rate adjusts. This calculator shows the initial payment, the balance still owed when the fixed period ends, and the new payment if the rate resets to the level you enter, re-amortized over the remaining term. A $300,000 5/1 ARM at 6% pays about $1,799 a month, then jumps if it resets to 8%.
ARMs start cheaper than fixed loans but carry the risk that rates rise at reset. Rate caps limit how much it can change per adjustment and over the life of the loan. Run a worst-case adjusted rate to see if you could still afford the payment.
reset payment = balance at reset re-amortized at the new rate
Frequently Asked Questions
What does 5/1 ARM mean?
The rate is fixed for 5 years, then adjusts once a year (the “1”). Other common intro periods are 3, 7 and 10 years.
How much can an ARM payment rise?
It depends on the new rate and the loan’s caps, which limit each adjustment and the lifetime increase. This calculator shows the payment at whatever adjusted rate you enter.
Is an ARM a good idea?
It can be if you’ll sell or refinance before the fixed period ends, or if you expect rates to fall. The risk is a higher payment if rates rise at reset.
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