Parquet Reader

Open .parquet files in VS Code and read them as a table — column types, per-column statistics, and full nested values, without leaving the editor and without loading the whole file into memory.

Features

Opens from the Explorer

Double-click any .parquet or .pq file. No command to run, no conversion step. The viewer is strictly read-only — it never writes back to your file.

The header reports what the file actually contains: row count, column count, file size, the compression codecs in use, and the writer that produced it.

Data tab

• 100 rows per page, with row numbers and a sticky two-line header showing each column name and its type
• Numeric columns are right-aligned; NULL is rendered distinctly from an empty string
• Nested columns (STRUCT, LIST, MAP, VARIANT) stay in a single column, rendered as JSON
• Long values are shortened to 200 characters in the grid, so a page stays fast to render

Cell detail

Click any cell to see its untruncated value in the pane below the table. Nested values are pretty-printed, and Copy puts the full value on your clipboard. Press Esc to close.

The full value is fetched on demand, one cell at a time — it is never included in the page payload, which is what keeps wide, deeply nested files responsive.

Schema tab

One row per leaf column, using dotted paths for nested fields. For each column: physical type, logical type, nullability, null count, min, max, and compressed size summed across all row groups. Columns whose writer omitted statistics show — rather than a misleading zero.

Remote files over HTTPS and S3

Run Parquet: Open Parquet from URL… from the Command Palette:

Then paste an https:// or s3:// URL:

• https:// — the server must support HTTP range requests. If it does not, the viewer says so instead of silently downloading the entire file.
• s3://bucket/key.parquet — signed by shelling out to aws s3 presign, so your existing AWS profile or SSO session does the signing and no credential ever passes through this extension. Presigned https:// URLs work directly, with no AWS CLI required.

Remote files are read the same way as local ones: only the footer and the data pages you are actually looking at cross the network.

Follows your theme

Light, dark, and high contrast themes are all supported — the viewer uses VS Code's own colour tokens rather than its own palette.

Performance

The viewer never reads a whole file. It reads the footer for metadata, then only the data pages needed for the rows on screen, using the file's offset index when one is present.

A 180 MB file with 1,244,896 rows stored in a single row group on S3 opens in 1–2 seconds, and page navigation stays under a second. Without offset-index support the same file took about 30 seconds to display its first page, because the first read had to pull every column chunk in the row group.

Files written without an offset index (for example, PyArrow without write_page_index=True) fall back to reading whole column chunks, which is correct but slower to open.

Requirements

• VS Code 1.90 or newer
• The AWS CLI, only if you want to open s3:// URLs. Everything else works out of the box.

Extension settings

None. The viewer has nothing to configure.

Known limitations

• Read-only. There is no sorting, filtering, or search yet.
• A BYTE_ARRAY column carrying no logical type is decoded as UTF-8 text by the underlying reader, so genuinely binary columns (hashes, blobs) display as unreadable text.
• Presigned S3 URLs expire after one hour. Reopening re-signs automatically, because the original s3:// URL is what gets stored, not the signature.

License

MIT — see LICENSE.