Free Moore–Marsden Calculator

Estimate the community property share of your home's equity based on principal paid during marriage. No signup—just numbers.

Disclaimer:

This simplified estimator is for informational purposes only and not legal advice. Outcomes depend on facts and law. Consult a qualified attorney.

Inputs

Original Purchase Price (required)

Down Payment (optional)

Principal Balance – At Date of Marriage (required)

Principal Balance – At Date of Separation (required)

Fair Market Value – At Date of Marriage (optional)

Fair Market Value – At Date of Separation (required)

Missing required: Original Purchase Price, Principal at Marriage, Principal at Separation, FMV at Separation

Who purchased this property?

Me My Spouse

I agree that this calculator is for estimation only and not legal advice.

Estimated Community Share

Enter the required fields to see the estimate.

How the calculation works

Courts look at mortgage principal reduction to determine what portion of home equity is attributable to community versus separate property. This estimator uses a ratio of principal paid during marriage to total principal paid, and applies it to equity at separation.

Principal paid during marriage ÷ Total principal paid = Community share ratio
Community share (est.) = Ratio × Equity at separation
Equity at separation ≈ FMV at separation − principal balance at separation

What-if scenarios

Large premarital payments reduce the community ratio.
Principal-only payments during marriage increase the community share.
Refinances and PMI may affect inputs; consult counsel.

Important notes

This is an educational estimator; it is not legal advice.
Jurisdiction-specific rules apply; Moore–Marsden is a California doctrine.
Bring your estimate to a qualified attorney for guidance.