ARM vs Fixed Mortgage Calculator

Loan Parameters

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Loan Details

Loan Amount

ARM Start Rate

Fixed Rate

ARM Fixed Period

Initial fixed-rate period

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ARM Cap Structure

Initial Cap

First adjustment max increase

Periodic Cap

Per-adjustment max increase

Lifetime Cap

Maximum total rate increase

Current Index Rate

e.g. 1-yr Treasury today

Lender Margin

Added to index at adjustment

Caps Notation

2/2/5

Initial / Periodic / Lifetime

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Scenario Options

Loan Term

Planned Exit Year

When you plan to sell or refi

Show Overpay Strategy

Pay fixed-rate amount on ARM

Cumulative Cost Over Time

Monthly Payment Comparison

Loan Balance Comparison

	ARM Payment			Fixed Comparison		Balance
Year	Rate	Req Pmt	vs Fixed	Fixed Pmt	Δ Monthly	ARM Bal	Fixed Bal

Year	Monthly Pmt	Annual Interest	Annual Principal	Balance End	Cumulative Paid	Total Interest

Standard ARM

$963,172

30-yr total paid

Overpay ARM

$991,738

but lower bal year 5–9

30-Yr Fixed

$851,014

30-yr total paid

Monthly P&I payment each year — note how the overpay ARM drops below fixed in year 6

Standard ARM

Overpay ARM

30-Yr Fixed

		Monthly Payments		Fixed	ARM Balance	Fixed Balance	Equity Edge
Year	Rate	ARM Req Pmt	Extra Pmt	Fixed Pmt	End of Year	End of Year	ARM vs Fixed