JSON Lines Converter

What JSON Lines is

JSON Lines, also called NDJSON, stores one valid JSON value on each line. It is commonly used for logs, streaming exports, bulk imports, and machine learning datasets because records can be processed line by line.

How this converter works

Use JSON to JSON Lines when you have a JSON array and want one compact record per line. Use JSON Lines to JSON when you want to inspect or edit line-delimited records as a formatted JSON array.

Blank lines and formatting

When converting from JSON Lines to JSON, you can ignore blank lines and choose the indentation level for the formatted result. Each non-empty line still needs to contain valid JSON, so malformed records will fail conversion.

When to use it

This tool is helpful when preparing event logs, webhook fixtures, search index documents, analytics exports, or LLM training samples that expect newline-delimited JSON instead of a single array payload.