100% local — no upload, no setup

Open and query Parquet files online – no installation needed

Inspect any .parquet file in your browser. Automatic schema detection, full SQL editor, 100% local.

Apache Parquet is the standard columnar format for analytical data. Queryfiles.app lets you open, browse and query .parquet files directly in your browser using DuckDB WebAssembly. No Python, no Spark, no server required.

Everything you need, nothing you don't

Automatic schema detection

Column names, data types and row counts are inferred automatically when you open a Parquet file.

Full SQL queries

Use the complete DuckDB SQL dialect to filter, aggregate and explore your Parquet data interactively.

Private by design

Your Parquet file never leaves your device. All reading and querying happens locally in your browser.

How it works

  1. 1

    Open a file

    Drag and drop a Parquet, CSV, JSON or XLSX file onto the home page, or click Browse to select it from your computer.

  2. 2

    Schema detected instantly

    Queryfiles.app reads the file locally and automatically infers column names, data types and an initial SQL query.

  3. 3

    Query with SQL

    Edit the SQL in the built-in editor powered by DuckDB, run queries and explore your data in real time, all inside your browser.

Frequently asked questions

What is a Parquet file?
Apache Parquet is a columnar storage format widely used in data engineering and analytics. It stores data column by column, making analytical queries very efficient. Files typically use the .parquet extension.
How do I open a .parquet file without Python or Spark?
Drag your .parquet file into Queryfiles.app. The file is read directly in your browser using DuckDB WebAssembly. No Python, Spark, or any server is required.
Can I run SQL queries on a Parquet file online?
Yes. Once open, Queryfiles.app provides a full SQL editor powered by DuckDB. You can run SELECT, WHERE, GROUP BY, aggregations and most standard SQL operations on your Parquet data.
Is my Parquet file uploaded to any server?
No. The file never leaves your machine. All reading and querying happen locally inside your browser's WebAssembly runtime.
Is there a file size limit for Parquet files?
Queryfiles.app handles files of several hundred megabytes on most modern browsers. Very large files may be slower depending on your available RAM.

Ready to explore your data?

Drop a file and start querying in seconds. No account, no upload, no setup.

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