JSONL Formatter
Pretty-print, minify, sort and deduplicate JSON Lines files.
JSONL input
Drop a file here
Drop a .jsonl or .ndjson file
Formatted output
About the JSONL Formatter
Make JSONL readable or make it strict. Expand each record for review, minify back to one-object-per-line, sort keys for stable diffs, drop invalid lines and remove duplicate records before training or importing.
Examples
Minify
{
"id": 1
}Output
{"id":1}Keyboard shortcuts
- Copy the main outputCtrl / ⌘ + Shift + C
- Download the resultCtrl / ⌘ + S
- Share this toolCtrl / ⌘ + Shift + S
- Reset the inputsAlt + R
- Open the tool search paletteCtrl / ⌘ + K
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Frequently asked questions
Version 1.0.0 · Updated 2026-08-14 · Runs entirely in your browser