Download a sample JSON Lines file of any size

Choose the data and the size, then download. Every line is one JSON record of realistic data, made on your device.

One record per line
Nothing is uploaded
100 KB to 1 GB
Free, no sign-up

Download a sample JSON Lines file in the size you need, from 100 KB to 1 GB. JSON Lines (also called JSONL or NDJSON) has one JSON record on each line, the format logs, exports and data pipelines often use. Each file is made for you from realistic data: orders, customers, products, blog posts, users or log events. To read one, use the JSON Lines Viewer.

What people use these files for

Test a log pipeline
Feed realistic log events, one per line, into a log shipper or your own reader.
Read a file line by line
Check that your code streams a file it can't load at once, one record at a time.
Load a database
Many databases and data warehouses import one JSON object per line.
Check an upload limit
Pick a size just under or over your limit to see how your form or API responds.

To read one, open it in the JSON Lines Viewer. To turn it into one JSON list, use JSON Lines to JSON.

How to use it

Choose what the file holds: orders, customers, products, blog posts, users or log events.
Choose a size from 100 KB to 1 GB, or type a custom size. The file holds whole records and stays within it.
Click Generate and download, or Open in GigaJSON instead to look inside it.

Private, and made for big files

This tool runs in your browser, in a background worker: the file is made on your computer and never uploaded, and nothing is kept after you leave. Files up to 1 GB are written in pieces, so the page keeps responding. Already loaded features keep working if your connection drops. Loading another tool or jq for the first time needs a connection. When one tool isn't enough, GigaJSON opens your data with a tree, a table, JSONPath/JMESPath/jq queries, transforms, diff and history.

Questions

What is a JSON Lines file?

A text file with one JSON value on each line, usually an object, and no brackets or commas between the lines. It's also called NDJSON (newline-delimited JSON); .jsonl and .ndjson are both common extensions.

Why use JSON Lines instead of JSON?

A program can read it one line at a time without loading the whole file, and new records can be added to the end. That's why logs, exports and data pipelines use it.

Can I open a 1 GB JSON Lines file?

Yes. The JSON Lines Viewer opens files up to 1 GB, depending on memory, and shows the records as a table or a tree.

Is the file the same every time?

Yes. The same size and data always give the same file.

Is anything uploaded?

No. The file is made in your browser and saved from there. Nothing is kept after you leave.