Free Property Data APIs & Datasets Compared (2026)
"Free" property data comes in a few shapes: a bulk dataset you download and own, a metered API with a small free tier, or raw county records you assemble yourself. Here's how they compare and when each one fits.
The options, compared
| Option | Access | Cost | License | Best for |
|---|---|---|---|---|
| Open bulk dataset (RealEstateDataset) | Direct download, no sign-up | Free | CC0 | Owning the data, bulk analysis |
| Self-serve API (incl. Straply) | API key | Free tier + paid | Per terms | Live, per-property lookups |
| Metered property APIs | API key | Small free tier, then metered | Restricted | Low-volume lookups |
| County assessor records | Per-county sites/exports | Free | Varies | One county, deep detail |
How to choose
Want to own the data and run unlimited analysis? Download the free bulk dataset — Parquet or CSV, per state/county/ZIP, CC0. Need a single property, always current? Use a self-serve API. Only care about one county and need every local field? The county assessor site is deepest, but you'll assemble it yourself.
RealEstateDataset is the free bulk option (146M records, CC0); Straply is the live API where each dataset row is an endpoint. See the full landscape in real estate data sources.
Frequently asked
What's the best free property data source?
Is there a completely free real estate API?
Can I use free property data commercially?