ARM Mortgage Calculator
Adjustable mortgages start on a teaser rate — enter balance, start rate, term, adjustment timing, and periodic cap for a one-adjustment payment sketch. Click any i for detail.
ARM inputs
Loan amount ($)
i
Loan amount
Remaining or original principal for payment math. |
|
|---|---|
Start rate (%)
i
Start rate
Initial note rate. |
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Term (years)
i
Term
Full amortization term. |
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Years until first adjust
i
Adjust period
Fixed-rate period before first change. |
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Periodic rate cap (%)
i
Periodic cap
Max increase at first adjustment in this sketch. |
How to use this calculator
- Enter loan amount and start rate.
- Set term and adjustment settings.
- Compare initial vs adjusted payment band.
Results explained
Headline is starting P&I; range shows payments after one capped rate move on the remaining term.
Quick reference: ARM sketch
Not a lender disclosure.
| Item | Detail |
|---|---|
| Initial PMT | PMT at start rate |
| Adjusted band | PMT at start ± cap on remaining term |
Indexes, margins, floors, and lifetime caps vary by loan.
How the estimate is built
Initial payment = standard PMT. After adjust period, re-amortize remaining term at start rate and at start rate + periodic cap.
Example scenario
A $360k 5/1 ARM at 5.75% might start near $2,101/mo; a +2% cap sketch on the remaining 25 years could land near $2,450/mo if rates jump.
FAQ
Is this my Loan Estimate?
No — educational band only.
What about indexes?
We apply your cap to the start rate as a simple stress sketch.
Payment shock?
Compare initial vs adjusted rows in the breakdown.