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NDJSON Record Filter

Filter newline-delimited JSON by a field condition, choose output fields and inspect rejected lines without losing the valid records.

Line decisionsEditable projectsLocal processing

Source → inspect → export

Preparing the worked example…

Your source & settings

Settings & options
Open your media file

Files stay in your browser. Try the built-in sample first.

Source text is limited to 1.5 million characters per editor; imported text files are limited to 1.5 MB.

Inspect your result

PREVIEW & EXPORT

Know what changed

One JSON value per nonempty line, maximum 10,000 lines. Numeric comparison requires finite numeric values. Bad JSON lines are reported and excluded.

    Choose another output above or open Export files.

    Explore the example

    Filter newline-delimited JSON by a field condition, choose output fields and inspect rejected lines without losing the valid records.

    What you can inspect

    • Line decisions — Line, Status.

    Keep the result you need

    Use the output selector to inspect each generated file, then download it. Save a project to keep source inputs and settings together. Result files and editable projects serve different purposes.

    Processing & file support

    Source text is limited to 1.5 million characters per editor; imported text files are limited to 1.5 MB.

    Your working session

    Processing runs locally in a worker with a 30-second cancellation limit. Undo and redo keep up to 20 edits in this tab. Project files include imported assets and are limited to 40 MiB. There is no automatic saving.

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    Using NDJSON Record Filter

    Filter newline-delimited JSON by a field condition, choose output fields and inspect rejected lines without losing the valid records.

    1. Start with the worked example in ndjson, then paste your own source or open a text file.
    2. Adjust filter field path, condition, comparison value, output fields · comma list; blank = all. Change one setting at a time so you can understand its effect.
    3. Choose “Process source”. Inspect the line decisions before using the result.
    4. Download the selected output, inspect other files in Export files and save a project if you want to reopen the same inputs.

    Example

    Try the built-in example, inspect line decisions and compare the result after changing one option.

    Questions & answers

    What does NDJSON Record Filter do?

    Filter newline-delimited JSON by a field condition, choose output fields and inspect rejected lines without losing the valid records.

    What are the important limitations?

    One JSON value per nonempty line, maximum 10,000 lines. Numeric comparison requires finite numeric values. Bad JSON lines are reported and excluded.

    Can I save and reopen my work?

    Yes. Save a project JSON file containing your inputs, settings and any imported assets. Projects are limited to 40 MiB. Undo/redo stores up to 20 edits in this session and is not saved in the project. There is no automatic saving.

    How do imports and output previews work?

    Source text is limited to 1.5 million characters per editor; imported text files are limited to 1.5 MB. Text previews show up to 150,000 characters; downloads include the complete output. Tables show 50 rows per page; CSV files include all rows.

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