JSON Array to JSON Lines
Input
[
{"user": "alex", "online": true},
{"user": "sam", "online": false}
]Example output
{"user":"alex","online":true}
{"user":"sam","online":false}JSON to JSON Lines & JSONL to JSON Converter
JSON & Data100% Client-SideReady
JSON
0 lines0 chars
0 B / 4.77 MB
Read-only
0 lines0 chars
0 B
About this tool, examples & FAQ
Convert bi-directionally between standard JSON arrays and line-delimited JSON (JSON Lines / NDJSON). Features empty line filtering, configurable indentation, and precise line-number error reporting.
Key facts
| Operations | JSON to JSON Lines (default) and JSON Lines to JSON |
|---|---|
| Standard Compliance | Compliant with JSON Lines (JSONL) and NDJSON specifications |
| Maximum Input | 5 MB |
| Execution Deadline | 3 s |
How to use
- Paste your JSON array or line-delimited JSON records into the input editor.
- Select your conversion direction: JSON → JSON Lines or JSON Lines → JSON.
- Adjust optional indentation (2 or 4 spaces) or blank line skipping.
- Click Convert (or press Ctrl/Cmd + Enter) to instantly transform the data.
- Copy or download your converted output as .json or .jsonl.
Examples
JSON Lines to JSON Array
Input
{"event":"login","ts":1001}
{"event":"logout","ts":1002}Example output
[
{
"event": "login",
"ts": 1001
},
{
"event": "logout",
"ts": 1002
}
]Edge cases
Line-by-line validation
When converting JSON Lines to JSON, each individual row must be a complete and valid JSON document. If any line contains invalid syntax, the exact line number is reported.
Trailing and blank lines
Streaming logs frequently contain blank lines between events or trailing newlines. The skipEmptyLines option automatically ignores them without failing the batch.
Single JSON objects
If a single JSON object is passed instead of an array, it is converted into a single-line JSONL record.
How it works
- Validates and parses JSON array elements or splits line-delimited text records.
- Compactly serializes each record into an isolated single line without unescaped newlines.
- Assembles parsed records into a clean JSON array with requested indentation.
- Executes purely within a local Web Worker without transmitting data.
Related workflows
JSON Formatter
Prettify, indent, and format JSON strings with customizable indentation and key sorting.
JSON ↔ CSV Converter
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JSON ↔ YAML Converter
Convert bi-directionally between JSON and YAML with strict alias and cycle protection, custom indentation, and swap support.
Frequently asked questions
What is the difference between JSON Lines, JSONL, and NDJSON?
They refer to the same concept: Newline Delimited JSON, where each line in the file is a separate, valid JSON value separated by a newline character (\n).
Why use JSON Lines instead of a regular JSON array?
JSON Lines allows streaming parsers, log aggregators, and big data systems (like Elasticsearch, Athena, BigQuery) to process records line-by-line without loading an entire multi-gigabyte array into memory.
Is my log or data payload uploaded to any server?
No. All parsing and conversion takes place entirely inside your browser via client-side Web Workers. Zero bytes are uploaded.
References
- JSON Lines Documentation & Specification — Standard JSON Lines format conventions and line-delimited rules
- NDJSON (Newline Delimited JSON) Specification — Newline Delimited JSON stream encoding standards