Turn pretty-printed JSON into a single-line string that is easier to paste into API clients, test scripts or examples.
Developer tool
JSON Stringify Tool
Paste JSON, validate it, convert it into a compact one-line string, or format it with clean indentation. This free JSON stringify tool runs in your browser and does not require sign-up.
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Useful for developers, testers, API work, config files and quick data cleanup.
Convert JSON to a compact string
Use this tool to turn readable, formatted JSON into a compact one-line string. You can also format JSON to make it easier to read.
What does JSON.stringify do?
JSON.stringify() converts a JavaScript value or JSON-compatible object into a JSON string. In everyday use, a JSON stringify tool is helpful when you need a compact JSON value for APIs, logs, test data, configuration, database fields or code examples.
This page can also validate your JSON. If the input is not valid JSON, the tool will show an error instead of producing an incorrect result.
Common JSON stringify use cases
Paste a JSON object and check whether it parses correctly before using it in code or sending it to an API.
Use the Format JSON button to convert compact JSON into a readable structure with 2-space indentation.
Frequently asked questions
Is this JSON stringify tool free?
Yes. This tool is free to use and runs directly in your browser. It does not require an account.
Does this tool store my JSON?
No. The current version processes JSON in your browser. Your input is not intentionally saved to a server.
What is the difference between stringify and format?
Stringify converts JSON into a compact one-line string. Format converts valid JSON into a more readable structure with indentation and line breaks.
Why do I get an invalid JSON error?
JSON requires double quotes around property names and string values. It does not allow trailing commas, comments or single-quoted strings.
Can I use this for JavaScript objects?
This page expects valid JSON, not arbitrary JavaScript object syntax. For example, property names must be wrapped in double quotes.