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Zillow vs Redfin: Which Has More Accurate Square Footage?
Buyers and sellers often notice that Zillow and Redfin show different square footage for the same home. Understanding where these numbers come from — and why they diverge — is key to knowing when to trust them and when to verify.
The short version
- Zillow: Square footage sourced from public records and MLS data. Can lag behind updates. Zestimate is square-footage-sensitive.
- Redfin: Also sources from public records and MLS. Generally more current MLS data in tech-forward markets. Same underlying data quality issues.
Zillow vs Redfin: at a glance
| Zillow | Redfin | |
|---|---|---|
| Data source | Public records + MLS | Public records + MLS |
| Physical measurement | No | No |
| Data freshness | Can lag by years | More current in tech markets |
| ANSI-compliant figures | No | No |
| Best use | Quick estimate | Quick estimate |
Where the numbers come from
Both Zillow and Redfin pull square footage from two primary sources: county tax assessor records and MLS (Multiple Listing Service) data. Neither company physically measures homes. The accuracy of their displayed square footage is entirely dependent on the accuracy of the underlying data sources.
County assessor records can be outdated, especially after additions or renovations. MLS data is more recent but depends on what the listing agent entered — which may or may not match a professional appraisal.
Why they sometimes differ
Zillow and Redfin may display different numbers for the same home because they weight their sources differently or pull from different regional MLS feeds. Zillow tends to default to public record data when it differs from MLS; Redfin sometimes shows MLS data more prominently in markets where they have direct feed agreements.
Neither is definitively more accurate. Both are as good as the data they receive.
Common errors
The most common sources of square footage error on both platforms: finished basement area included in living area (which ANSI Z765 does not allow); garage square footage accidentally included; unverified seller-entered figures from expired listings that persist in the database; and assessor records that were never updated after unpermitted additions.
How to verify
If square footage matters for a transaction — and it usually does, since it affects price per square foot, appraisal value, and tax assessment — verify with a professional appraisal, a CubiCasa or iGUIDE scan, or by uploading a to-scale floor plan to a measurement tool. Don't rely solely on Zillow or Redfin for any transaction where accuracy is critical.
Already have the floor plan?
If you have a floor plan of the property — from an appraisal, a listing package, or a scan service — you can verify or recalculate the square footage yourself using PlanSnapper. Upload the floor plan, set the scale, trace the perimeter, and get a measurement in minutes.