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Parquet Viewer

Drop a Parquet file and look at the first rows, with a row limit you set. See the schema and row count too. Nothing is uploaded.

Drop a .parquet file, or choose one. Nothing is uploaded.

Why the viewer caps the rows

A Parquet file can hold millions of rows, and a browser tab cannot render them all. The viewer shows the first N rows only. Pick 50, 100, 150, 250, or 500 from the presets, or type your own number up to 5,000. The heading always says how many rows are on screen out of the total in the file.

The cap also keeps the read cheap. The tool reads the footer for the schema and row count, then only the pages that hold the rows you asked for. Later row groups are never decoded.

Schema and column types

Under the table is the schema: each column's physical type, its logical type when the file has one (UTF8, timestamp, decimal), and whether nulls are allowed. Nested structs and lists are indented under their parent. Use the column filter to narrow a wide table to the columns you care about.

Compression and awkward values

Uncompressed and Snappy files are read in full. Gzip, Zstd, and other codecs show the schema and row count, but the rows are not decoded. Large integers appear as exact decimal strings, dates as ISO-8601, binary as base64, and nested values as JSON.

To export the whole file, use Parquet to CSV. To build a Parquet file, use CSV to Parquet. Nothing you open here is uploaded.

FAQ

Is my Parquet file uploaded?

No. The file is read in your browser and never leaves your device.

How many rows can I view?

You choose the row limit, from 1 to 5,000. The presets are 50, 100, 150, 250, and 500. The viewer reads only the pages that hold those rows.

Which compression can it read?

Uncompressed and Snappy. For other codecs the schema and row count are shown and the rows are not decoded.

Can I export the data?

Yes. Use the Parquet to CSV tool to export the full file as CSV or JSON.

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