United States Guides Parquet vs CSV for Property Data

Parquet vs CSV for Property Data

Both formats hold the same properties. The difference is what they carry, how big they are, and how fast they query.

The short answer

Use Parquet if you're analyzing data in code (pandas, DuckDB, Polars, Spark) or you want the full schema including price and tax history. Use CSV if you want to open it in a spreadsheet or feed a tool that only speaks CSV.

What each carries

  • Parquet — all 32 columns, including the nested price_history and tax_history arrays. A columnar, compressed binary format.
  • CSV — the same records as a flat table, minus the two nested history columns (a flat file can't hold arrays cleanly).

Size and speed

Parquet is columnar and compressed, so the same data is often several times smaller on disk than CSV, and queries that touch a few columns read only those columns — much faster on large files. CSV is row-oriented plain text: universally readable, but bigger and slower to scan.

Opening each

Parquet: pd.read_parquet("file.parquet") in pandas, or SELECT * FROM 'file.parquet' in DuckDB — no import step. CSV opens in Excel, Google Sheets, or any language's CSV reader. Full walkthrough in how to download property data.

Frequently asked

Should I download Parquet or CSV?

Parquet for analysis in code or if you want price/tax history; CSV for spreadsheets or tools that only accept CSV. The property records are identical in both.

Can Excel open a Parquet file?

Not directly. Excel opens CSV. For Parquet, use pandas, DuckDB, Polars, or a Parquet viewer — or just download the CSV version.

Why is Parquet smaller than CSV?

Parquet is a compressed, columnar binary format, so the same data takes far less space than row-oriented plain-text CSV — and it's faster to query.

Does the CSV include price history?

No. The nested price_history and tax_history arrays are in the Parquet file only; CSV carries the flat columns.
Grab a file and try both
Browse the downloads →

RELATED · GUIDES

See all guides →