Convert Case in JSON Files Online
Convert text columns to UPPERCASE, lowercase, or Title Case in JSON files directly in your browser. Apply case conversion to any or all text columns at once — no upload required.
Drop your .json file here
or click to browse — max 50 MB
About this tool
Convert text columns in a JSON file to UPPERCASE, lowercase, or Title Case in one click. Standardise inconsistent capitalisation before merging datasets or loading into a system with case-sensitive matching.
Frequently Asked Questions
What case options are available for JSON files?
UPPERCASE (all letters capitalised), lowercase (all letters lowercased), and Title Case (first letter of each word capitalised, rest lowercased).
Which columns are converted when I change case in a JSON file?
Only text (VARCHAR) columns. Numeric, boolean, and date columns are not affected.
Can I apply different case styles to different columns in the same JSON file?
The tool applies one case mode to all selected columns in a single run. For mixed requirements, run the tool twice — once per case style — on different column selections, then use the Merge tool to recombine.
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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