JSON to Java
Generate Java records from any JSON sample.
Three steps, no reading required.
Paste your input
Drop text, code, or data into the input pane — from an API response, a file, anywhere.
See it process
The result updates instantly as you type.
Copy the result
Grab the output with Copy or Download, or fix the error shown if the input is invalid.
Try it with a sample.
{"id":1,"name":"Ada","active":true,"roles":["admin","user"],"address":{"city":"London"}}Upload & hope
- Sends your input to a server to process it
- Asks for an account after a few free uses
- Limits input size on the free tier
Runs where you are
- Processes everything inside your browser tab
- No account, ever
- No artificial size limit
Questions worth answering upfront.
No. Records are generated entirely in your browser. Your JSON is never uploaded, stored, or logged.
It generates modern Java records (Java 16+), which are concise and immutable. A @JsonProperty annotation is added when the component name differs from the JSON key for Jackson.
Keys become camelCase components following Java convention. When the name differs from the JSON key, a Jackson @JsonProperty annotation preserves the original key.
When an array of objects has a key missing from some elements, the component uses a boxed type (Integer, Double, Boolean) so it can be null.
Yes. Every tool on DevUtilsNow is free to use with no account required.
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Guides that pair with this tool
How to Generate Java Records from JSON
Turn a JSON sample into Java records — camelCase components, Jackson @JsonProperty, boxed types for nullable fields, and List for arrays.
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