Zestimate guide
Zestimate vs appraisal: why they are different numbers
One is an algorithm that has never been inside your home. The other is a licensed human standing in it. Here is when each one matters.
People treat the Zestimate and an appraisal as two opinions of the same thing. They are not. They are produced by completely different processes, for different purposes — which is exactly why they so often disagree.
What each one actually is
- Appraisal — a licensed appraiser physically inspects your home, adjusts comparable sales for condition and features, and produces a lender-grade valuation as of a specific date. It is what mortgages rely on.
- Zestimate — an automated model that estimates value from public records and nearby sales. It has never been inside your home and makes no human, property-specific judgment.
Why they diverge
The appraisal sees condition, renovations, and finishes the model can only guess at. The Zestimate, meanwhile, can lean on comps from the wrong area or stale facts. So a renovated home is often appraised well above its Zestimate, while a home compared to nicer neighbors can be estimated above what it would appraise for.
Which should you trust, and when
For a sale, refinance, or any formal decision, the appraisal (or an agent's CMA) is the authoritative number. The Zestimate is a free, directional gut-check — useful for spotting when something is off, not for setting a price. The smart move is to understand why your Zestimate is off and fix the inputs before an appraisal or listing, so the public number is not working against you. See the correction guide.
Audit your Zestimate — free.
Run your address through an independent audit. We check the facts on file, compare every public AVM, and run ClearComp™ to show whether out-of-town comps are dragging your number — in plain English, no sign-up.
Run my free audit →Frequently asked questions
Is a Zestimate ever as accurate as an appraisal?
No. They are different tools. An appraisal is an in-person, licensed valuation; the Zestimate is an automated estimate from public data. Treat the Zestimate as a rough reference, never a substitute for an appraisal.
Will a lender use my Zestimate?
No. Lenders require a formal appraisal (or in some cases an approved AVM through their own process). The Zestimate has no role in mortgage underwriting.
My appraisal is higher than my Zestimate — can I fix the Zestimate?
Often yes. A low Zestimate next to a higher appraisal usually points to wrong facts or mismatched comps. Correcting those inputs can move the estimate closer to reality.