ARM Mortgage Calculator

v1.3

Estimate initial and reset payments on an adjustable-rate mortgage.

Last updated · Last reviewed

Inputs

USD
%
mo

e.g. 60 for a 5/1 ARM, 84 for a 7/1 ARM.

%
%
%

Maximum rate rise at the first reset (commonly 2%).

Result

Initial Payment

$2,271.16

Fixed at 5.5% for 60 months

Estimated Reset Rate7.5%
Payment After Reset$2,733.10
Payment Change+$461.95

Saved calculations remain on this device unless you choose to share them. No tracking, no account needed.

Formula

Reset rate = min(index + margin, initial + cap). Payment recalculated on remaining balance over remaining term.

How it works

Estimate initial and reset payments on an adjustable-rate mortgage.

Example

Example: 5/1 ARM at 5.5% resetting into ~7.5%.

Official Sources & References

The formulas, rates and definitions used by this calculator are aligned with the following official sources:

We use only primary sources — regulators, standards bodies and scheme operators. See our full sourcing policy for details. Sources & References Policy · Calculator Methodology · How We Verify Formulas

Trust & Accuracy

Formula verified

Verified against standard amortisation & Truth-in-Lending (Reg Z) conventions.

Last reviewed

June 27, 2026

Accuracy tested

Edge cases tested, formula validation and manual verification completed.

Available for

United States, Canada, United Kingdom, Australia, India, European Union.

Currency support

USD · INR · CAD · AUD · GBP · EUR

Privacy

No information entered into this calculator is stored on our servers unless you explicitly choose to save or share your calculation.

Print, share & save

Use the Save, Share, Copy, PDF, CSV and Print actions under the result panel.

Accessibility

Keyboard navigable, screen-reader friendly labels, responsive on mobile and desktop.

Learn more: How we verify formulas · How we test accuracy · Methodology · Editorial policy

Recent Updates

We continuously review and improve our calculators to keep formulas, assumptions and references accurate.

View change log (4)Show
  1. v1.3

    Added Trust & Accuracy panel and machine-readable change log.

  2. v1.2

    Added Save, Share, PDF, CSV and Print actions to results.

  3. v1.1

    Added global currency selector (USD, INR, CAD, AUD, GBP, EUR).

  4. v1.0

    Initial calculator release with verified formulas and Official Sources.

Frequently Asked Questions

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Disclaimer: Results are estimates for informational purposes only and should not be considered financial, medical, legal, or professional advice. Always consult a qualified professional before making decisions.