Problem
How to Open a .parquet File on Windows
The file has no icon. Double-clicking offers to search the Microsoft Store. The first ten search results tell you to install Python and pandas, which is a lot of ceremony for looking at a table.
The short answer
Open Data Explorer in DataTray and drop the .parquet file in — or the folder, if it came as
one. The rows appear immediately, with the column types Parquet already recorded. Export to
.xlsx or CSV if you need to pass it on. Nothing else to install.
Why Windows cannot open it
Parquet is a binary, columnar, compressed format built for analytics engines rather than for
people. There is no shell handler, no preview, and no Notepad-equivalent that will show you
anything useful — opening it in a text editor gives you a screenful of control characters and the
word PAR1.
That is not a broken file. It is a format that assumes the reader is a query engine.
Point at the folder, not the file
The most common mistake worth avoiding.
A large Parquet dataset is usually a directory of parts — part-00000.parquet,
part-00001.parquet — sometimes nested in folders named region=West/ or dt=2026-08-01/.
Those parts are one table that has been split, and the folder names are frequently a column in
their own right.
Open a single part and you get a slice, with nothing on screen telling you the other ninety-nine exist. Open the directory and you get the whole table, partition columns included.
What you can do once it opens
Look at it. Rows, column types, null rates, ranges, top values. Parquet stores its schema, so none of that has to be guessed.
Query it. The SQL tab reads files by path, so SELECT … FROM 'data/*.parquet' works, as does
joining a Parquet file to a CSV.
Convert it. To .xlsx for somebody in a spreadsheet, or to CSV for a tool that wants text.
Both keep the types Parquet recorded, which is the advantage of converting from Parquet rather
than to it.
Two things to expect
The CSV will be much bigger. You are throwing away columnar compression and the schema. A 200 MB Parquet file can be well over a gigabyte as CSV. If size matters, filter first and export the slice.
Excel's row limit still applies. Parquet datasets are frequently far larger than 1,048,576
rows. Converting the whole thing to .xlsx will silently truncate it — filter or split before
you convert, which DataTray will do in the same run.
Why you keep receiving these
Because Parquet is what data warehouses and pipelines emit. It is smaller, faster to query, and keeps its types — all of which matter enormously to the system that produced it and not at all to a person who just wants to see the numbers.
The handoff between those two worlds is exactly where this problem lives, and it is worth having one tool that sits on both sides of it.
Every other free way to do this asks you to upload the file first, or to install a programming language. Neither is necessary to look at a table.
Do this in one pass with — Data Explorer
Read-only, always. Open a CSV, Excel workbook, Parquet directory or JSON file of any size and look at the rows — then switch to Columns for a full data profile: what every column actually holds, where the nulls and the mixed types and the outliers are, a data-quality read on each one, and a data dictionary you can hand to someone. A third tab takes SQL if you want it, and never asks you to write any if you don’t. Nothing here modifies the file; the only things written are the exports and reports you ask for. Learn more about the Data Explorer.
Windows 10/11 (x64) · Free · No account