Extract Head of NDJSON Files Online

What is the difference between head and sample for NDJSON files?

Head always returns the first N rows in their original order. Sample can return a random subset. Use head when you need the earliest records in time-ordered data or a deterministic slice.

Is extracting the head of a large NDJSON file fast?

Very fast. The tool reads only the first N rows and stops — it does not need to scan the entire file.

Can I choose which columns to include when extracting the head of a NDJSON file?

The output includes all columns from the original. Run the result through the Columns tool if you need to drop unwanted columns.

Is my data private?

Yes — completely. Your file is never uploaded to any server. Everything runs locally in your browser using WebAssembly — processing happens entirely inside your tab. Once you close the tab, nothing is retained.

What is the maximum file size?

The free limit is 50 MB. For larger files, performance depends on your device's available memory — most modern machines handle 500 MB to 1 GB comfortably.