How are numbers typed?

Whole numbers become long and numbers with a decimal point become double. Change to int or float manually if you prefer a narrower type.

What happens with null or empty arrays?

null values map to Object and empty arrays to List , since their type can't be inferred from the sample.

How are nested objects handled?

Each nested object becomes its own class. An import for java.util.List is added when any list field is generated.

Is my JSON sent anywhere?

No. Conversion happens entirely in your browser; nothing is uploaded.

JSON to Java Class (POJO) Converter

Paste any JSON object or array and get ready-to-use Java `class` definitions (POJOs) with typed fields (String, long, double, boolean, List<...>) and separate classes for nested objects. Everything runs locally in your browser — your JSON is never uploaded.

—

Root class nameJSON input

Java classes

import java.util.List;

public class AutoGenerated {
    public String name;
    public long age;
    public boolean active;
    public List<String> tags;
    public Meta meta;
}

public class Meta {
    public String id;
}

How to use

Paste or type your JSON into the input box.
Optionally rename the root class (defaults to AutoGenerated).
Copy the generated classes from the output box.

Frequently asked questions

How are numbers typed?: Whole numbers become long and numbers with a decimal point become double. Change to int or float manually if you prefer a narrower type.
What happens with null or empty arrays?: null values map to Object and empty arrays to List<Object>, since their type can't be inferred from the sample.
How are nested objects handled?: Each nested object becomes its own class. An import for java.util.List is added when any list field is generated.
Is my JSON sent anywhere?: No. Conversion happens entirely in your browser; nothing is uploaded.

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