JSON Rename Keys Tool – Rename JSON Keys Online
Rename selected keys across nested JSON structures in bulk. Our free JSON Rename Keys Tool makes API response normalization and data migration fast and error-free.
About JSON Rename Keys
Working with APIs often means dealing with inconsistent key naming conventions. Snake_case from one service, camelCase from another. This tool lets you bulk rename JSON keys to match your application's expected format without manual editing.
How it works
Paste your JSON and define rename rules by specifying old key names and their new counterparts. The tool processes each rule and applies the transformation across your entire JSON structure.
Enable the recursive option to rename keys at all nesting levels. This is useful when the same key appears in multiple nested objects and you want consistent renaming throughout.
When you'd use this
You're integrating a third-party API that returns user_name and user_email, but your frontend expects username and email. Instead of writing transformation code, quickly rename the keys here and use the output directly.
Note that this tool performs simple key replacement. If you need conditional renaming or value-based transformations, you'll need a more advanced data transformation solution.
Questions
Does this rename keys in nested objects?
Yes, when you enable the Recursive checkbox, the tool renames matching keys at all nesting levels throughout your JSON structure.
Can I rename multiple keys at once?
Absolutely. Click Add Rule to create as many rename mappings as you need. Each rule is applied in sequence to transform your JSON.
What happens if old and new key names are the same?
The tool will simply keep the existing key name. There's no error, but the rule effectively does nothing in that case.
Are arrays handled correctly?
Yes. When recursive mode is on, the tool processes objects inside arrays and renames matching keys within those nested objects.
Can I download the renamed JSON?
Yes. Use the Download button to save your renamed JSON as a file, or click Copy to paste it directly into your code.