What is JSON.stringify()?

JSON.stringify() is a JavaScript function that converts a JavaScript value (object, array, number, string, etc.) into a JSON string. It is the standard way to serialize data for storage or transmission in JavaScript applications.

What is doubly-stringified JSON?

Doubly-stringified JSON occurs when JSON.stringify() is called twice on the same data, producing a string that contains an escaped JSON string. This often happens accidentally in logging or when building API payloads. The reverse mode in this tool helps diagnose it.

What does the "string literal" option do?

It wraps the JSON output in double quotes and escapes internal quotes and newlines, producing output you can paste directly into JavaScript or TypeScript source code as a string constant.

Are JSON.stringify() and JSON formatting the same thing?

They produce similar output, but JSON.stringify() is a JavaScript runtime function while JSON formatting is a display operation. This tool simulates JSON.stringify() behavior exactly, including how it handles undefined, functions, and Symbol values (they are omitted).

JSON Stringify

Explore JSON.stringify() output with indent options, string literal wrapping, and a reverse parse mode

Input

JSON Input

Output

Stringified Output

Indent:

Wrap as string literal

Shortcuts: Ctrl+Enter run · Ctrl+L clear · Ctrl+D download

About JSON Stringify

This tool shows exactly what `JSON.stringify()` produces for your input, with control over the indentation level and optional string-literal wrapping for embedding in JavaScript source code. A reverse "parse" mode lets you paste a stringified JSON string and see the parsed object — useful for debugging doubly-encoded JSON in logs or API responses.

✓Shows raw JSON.stringify() output with configurable indent levels (0, 2, 4)
✓String-literal mode wraps the output in quotes and escapes it for pasting into JavaScript code
✓Reverse mode: paste a stringified JSON string to parse and display the original object
✓Useful for debugging doubly-stringified JSON and log output

JSON Stringify

About JSON Stringify

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