parquet.to is a tool that allows users to inspect Apache Parquet files in their browser. It enables users to drop one or more .parquet files, browse rows, filter, and export the data. The tool runs entirely in the browser, and files are processed locally without uploading. parquet.to provides various features such as viewing, querying, charting, and converting Parquet files to different formats like CSV, JSON, XLSX, SQL, XML, NDJSON, TSV, MD, and HTML.