---
title: ".jsonl file — what it is and how to open it"
description: "A .jsonl file is a JSON Lines. One complete JSON object per line — a format built for streaming large data sets. How to open one on Windows, macOS and Linux, and what to convert it to."
url: https://atoneplace.net/file/jsonl/
site: "At One Place"
---

# .jsonl files

**.jsonl file: JSON Lines**

One complete JSON object per line — a format built for streaming large data sets.

## What opens a .jsonl file

- **Windows:** Visual Studio Code, Notepad++, jq (command line)
- **macOS:** Visual Studio Code, jq (command line), BBEdit
- **Linux:** Visual Studio Code, jq, Text Editor (built in)

## What a .jsonl file is

JSON Lines stores a sequence of records as independent JSON objects separated by newlines, so a program can process a huge file one line at a time instead of loading it whole. Machine learning data sets, log pipelines and LLM training corpora use it heavily. It is plain text: any editor opens it, though a multi-gigabyte file wants a streaming tool such as jq rather than a GUI.

## Converting it

A .jsonl file is commonly converted to .json, .csv, .parquet or .ndjson. It is a plain text format, so any text editor can open and edit it directly.

## Details

- **Extension:** .jsonl
- **Full name:** JSON Lines
- **Category:** Data
- **MIME type:** application/jsonl
- **Created by:** Community convention
- **Format:** Plain text

## Common questions

### How do I open a .jsonl file?

On Windows use Visual Studio Code; on macOS use Visual Studio Code; on Linux use Visual Studio Code. One complete JSON object per line — a format built for streaming large data sets.

### What is a .jsonl file?

JSON Lines. JSON Lines stores a sequence of records as independent JSON objects separated by newlines, so a program can process a huge file one line at a time instead of loading it whole. Machine learning data sets, log pipelines and LLM training corpora use it heavily.

### Can I convert a .jsonl file?

Yes. It is usually converted to .json, .csv, .parquet or .ndjson, either by exporting from one of the programs listed above or with a format converter.

## Related pages

- [.csv — Comma-Separated Values](https://atoneplace.net/file/csv/)
- [.json — JavaScript Object Notation](https://atoneplace.net/file/json/)
- [.xml — Extensible Markup Language](https://atoneplace.net/file/xml/)
- [.yaml — YAML Data File](https://atoneplace.net/file/yaml/)
- [.log — Log File](https://atoneplace.net/file/log/)
- [.torrent — BitTorrent Metainfo File](https://atoneplace.net/file/torrent/)
- [.dat — Generic Data File](https://atoneplace.net/file/dat/)
- [.vcf — vCard Contact File](https://atoneplace.net/file/vcf/)
- [.sql — SQL Script](https://atoneplace.net/file/sql/)
- [.ics — iCalendar Event](https://atoneplace.net/file/ics/)
- [.sqlite — SQLite Database](https://atoneplace.net/file/sqlite/)
- [.db — Generic Database File](https://atoneplace.net/file/db/)

## Sources

- Media Types Registry — IANA (https://www.iana.org/assignments/media-types/)
- Official vendor product documentation — At One Place (/about/)