Manage Columns in JSON Files Online
Drop or select specific columns from JSON files directly in your browser. No upload required.
About this tool
Select and reorder columns from JSON files without writing any code. Tick the columns you want to keep, drag to reorder, and download the result. Runs entirely in your browser.
Frequently Asked Questions
Can I reorder columns in a JSON file as well as remove them?
Yes. Columns appear in the output in the order you select them. Deselect all and reselect in a different order to change column positions.
What happens to data in the columns I drop from a JSON file?
Dropped columns are excluded from the output. The original file is unchanged — you can always re-run the tool with a different selection.
Does selecting columns from a JSON file change data types?
No. Data types are preserved exactly as they appear in the original file.
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.
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