What Zestimate accuracy means
A Zestimate is Zillow's automated estimate of a home's market value. Zillow measures it by its median error, the gap between the Zestimate and the final sale price.
Half of the estimates fall inside that gap, and the other half fall outside it. So a median error of 1.77% still leaves many homes further off.
- Median error: half of estimates land within this share of the sale price.
- On-market homes: listed homes, where the listing adds fresh data.
- Off-market homes: homes with no listing, where the estimate has less to work from.
- Range: the low and high ends around an estimate, wider when the estimate is less certain.
A real example from a Homesage.ai report
We ran a Full Property Report on a single-family property listed for sale in Atlanta, Georgia, on 23 October 2026. We read its Zillow page the same day.
| What each source shows | This property |
|---|---|
| List price | $624,900 |
| Zestimate on 23 October 2026 | $608,200 |
| Zillow estimated sales range | $578,000 to $639,000 |
| Homesage.ai estimated value | $670,392 |
| Homesage.ai range and confidence | $631,000 to $697,000, medium confidence |
| Condition score | Excellent |
| Comparable sales in the report | 5, from $510,000 to $652,700, sold January to May 2026 |
The 2 estimates sit $62,192 apart, about 10% of the Zestimate. Their ranges overlap only between $631,000 and $639,000.
The list price sits inside Zillow's range and $6,100 below the low end of ours. So one estimate calls the asking price fair, and the other calls it low.
Two estimates can both look precise and still point to different offers.
The report shows its estimate as a range with a confidence level, not a single figure.
Zillow puts its median error for listed homes in the Atlanta metro at 1.53%. On a $608,200 Zestimate, that is about $9,305.
How to work out how far to trust a home value estimate
- Read the full range around the middle figure. Here Zillow's runs from $578,000 to $639,000.
- Check how certain the estimate is. Our report rates this one medium confidence, with a $66,000 range.
- Date the comparable sales. The 5 behind our estimate sold from January to May 2026.
- Check whether the estimate knows the property's condition. This report rates it Excellent, and 3 of the 5 comparable sales were rated Good.
- Get a second view from recent sales, an agent, or an appraisal before you make an offer.
Why home value estimates differ
Data is the first reason. Each estimate reads its own mix of sales, listings, and public records, so two sources start from different facts.
Timing is the second. A sale from 9 months ago reflects 9-month-old prices. Condition is the third. An estimate that cannot see a renovated kitchen prices the property like a dated one.
Common home value estimate mistakes to avoid
- Reading one figure as the value: An estimate is a range. On the Atlanta property, the 2 ranges together run from $578,000 to $697,000.
- Comparing on-market and off-market accuracy: Zillow reports 1.77% for listed homes and 7.20% for off-market homes. Use the figure that matches the property.
- Treating an estimate as an appraisal: An appraisal comes from a licensed appraiser who visits the property.
- Picking the estimate you like best: The 2 estimates here sit $62,192 apart. Check the comparable sales behind each one before you offer.
Frequently asked questions
How accurate is the Zestimate?
Why does a property have no Zestimate?
Why do Zillow and other home value estimates differ?
Is an online home value estimate the same as an appraisal?
Which estimate should I use for an offer?
Ask Sage what a property is worth
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- Homesage.ai Full Property Report for a single-family property in Atlanta, Georgia (30318), generated 2026-10-23.
- Zillow, Zestimate accuracy, read 2026-10-23, accuracy table refreshed 2026-09-30.
- Zillow property page for the same listing, read 2026-10-23. Not linked, because the page shows the street address.
