AZ Tools

JSON Lines (NDJSON) Viewer

File

JSON Lines / NDJSON is one JSON object per line, used by streaming logs, ML datasets, and tail-friendly pipelines. This viewer parses every line independently — so a single malformed line doesn't poison the whole file — and surfaces both the parsed table and the bad lines with their JSON error message. A `field:value` filter narrows by content (top-level key or `nested.path` are both supported), and a column picker keeps only the fields you care about for the re-export. Everything runs in the browser; nothing is uploaded.

How to use

  1. Paste lines or drop a `.jsonl` / `.ndjson` file. The table shows automatically.
  2. Filter with `field:value` (substring match) or plain text (matches anywhere in the JSON).
  3. Pick columns in the second box to keep — leave blank to show all keys discovered.

Frequently asked questions

What happens to malformed lines?
They're listed at the bottom with their line number and the JSON parse error. Valid lines on either side of a bad one are still parsed and displayed normally.
Can I filter on nested fields?
Yes — use dotted paths like `user.email:alice` or `events.0.type:login`. The path walks both objects and arrays.

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