How to use this tool
- Strict NDJSON uses one JSON value per line; JSON to NDJSON needs a top-level array. Switching keeps the source.
- Choose an operation and run it.
- Review before export.
Private by default
NDJSON Toolkit (All-in-One)
Pretty, Validate, Minify, NDJSON to JSON, or JSON to NDJSON. Pretty returns .txt, not NDJSON.
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UTF-8Ln 1, Col 1
UTF-8—
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Your data stays in this browserInstantNo server round trips
PrivateBrowser-side processing
AuditableDocumented semantics
PortableCorrectly typed downloads
Category
NDJSON Toolkit: How to use this tool
Validate JSON Lines, pretty-print records, minify NDJSON, or convert between NDJSON and JSON arrays in one workspace.
Pretty, Validate, Minify, NDJSON to JSON, or JSON to NDJSON. Pretty returns .txt, not NDJSON.
Open guide and examples
Example to try
Input NDJSON
{"id":1,"event":"created"}
{"id":2,"event":"updated","active":true}
["heartbeat",1712345678]Result
{
"id": 1,
"event": "created"
}
{
"id": 2,
"event": "updated",
"active": true
}
[
"heartbeat",
1712345678
]Learn
Frequently asked questions
Does this tool upload my JSON?
Processing is local; URL import contacts that address.
What happens when the JSON is invalid?
Invalid NDJSON reports line numbers without partial output.
What does NDJSON Toolkit produce?
Output is text, a report, NDJSON, or a JSON array.
What limitation applies to NDJSON Toolkit?
Conversions reject duplicate names and precision-losing numbers; limits apply.