ON-DEVICE PROCESSING
JSON Lines Validator
Validate newline-delimited JSON and report errors.
Find invalid entries in newline-delimited JSON
How to use this tool
Paste one JSON value per nonempty line. The validator parses each line separately and reports physical line numbers when a line fails. For example, {"id":1} parses while {id:2} fails because JSON property names require quotes. Blank lines are ignored when counting records.
Check the result
A successful syntax check does not prove a record has the required fields, valid dates, or a consistent schema. Multiline pretty-printed JSON is not JSON Lines. For a single JSON document, use JSON Formatter & Validator instead.
About JSON Lines Validator
Validate newline-delimited JSON and report errors.
How to use it
Paste one JSON value per nonempty line. The validator parses each line separately and reports physical line numbers when a line fails. For example, {"id":1} parses while {id:2} fails because JSON property names require quotes. Blank lines are ignored when counting records.
Before you use the result
A successful syntax check does not prove a record has the required fields, valid dates, or a consistent schema. Multiline pretty-printed JSON is not JSON Lines. For a single JSON document, use JSON Formatter & Validator instead.
Frequently asked questions
Can I save my result?
Run the tool, then use its download control. Text results can be saved as a file; image and audio tools show their available export links after generation. A disabled download means a new result is needed.
Are my inputs uploaded?
The tool processes your input in this browser tab. Opening the page downloads the site assets; your tool inputs are not sent to a processing server. Save your result before closing the tab.
How do I start again?
Use Restore example to reset the editable fields, then run the tool again. Changing input invalidates the previous export so that you can generate a fresh result.