JSON Parse and Stringify Converter

How to use the json stringify / parse

1. Paste your text into the Input text field.
2. Choose Parse to convert a string to JSON, or Stringify to serialize a value.
3. Set the number of Indent spaces for the output formatting.
4. The result appears immediately below as you type.

How json parse works

The built-in JSON.parse() method reads a text string and constructs the corresponding JavaScript value. The input must follow strict JSON syntax: double quotes around keys and string values, no trailing commas, and no comments. For example, parsing the string {"count":42} produces an object with a numeric property. If the text violates the grammar, the parser throws a SyntaxError that this tool catches and displays.

When you select the parse direction, the tool first parses the raw string into a value, then immediately re-serializes it using JSON.stringify with your chosen indentation. This round-trip normalizes whitespace and confirms the input was valid JSON.

Using json stringify

The JSON.stringify() method converts a value into a JSON text string. It accepts three arguments: the value, an optional replacer, and an optional space parameter for indentation. In this tool, the space parameter is controlled by the indent field. Setting it to 0 produces a minified single-line string, while 2 or 4 adds line breaks and leading spaces.

Because browsers cannot safely evaluate arbitrary JavaScript objects from user input, the stringify mode here also expects valid JSON text. It parses the input first, then re-stringifies it with the requested formatting. To convert actual JavaScript object literals (with unquoted keys or single quotes), use a dedicated code formatter or wrap your data in valid JSON first.

Common conversion examples

Primitive values like strings, numbers, booleans, and null are valid JSON on their own. You can parse or stringify them without wrapping them in an object or array.

Edge cases and common mistakes

Several patterns cause a string to JSON conversion to fail. Single quotes ('key') are not valid JSON; all strings must use double quotes. Trailing commas after the last element in an object or array will throw an error. Comments, both // and /* */, are not part of the JSON specification and must be removed before parsing.

Special numeric values like NaN and Infinity are not representable in JSON. When JSON.stringify encounters them inside an object, it converts them to null. If they appear at the top level, the result is undefined. Keep this in mind when serializing data from mathematical computations.

For validating complex payloads before sharing them with an API, consider pairing this tool with a json validator to check structure and schema compliance.

Related formats and tools

JSON is often converted to other tabular or markup formats for reporting. If you need to turn an array of objects into comma-separated values, a json to csv converter handles that mapping. For viewing deeply nested structures without editing them, a json viewer provides a collapsible tree interface.

When working with configuration files, you might also encounter YAML or XML. Converting between these formats requires different parsers, but the underlying principle remains the same: read the source text into a language-native data structure, then serialize it into the target format.

Worked examples

Each result below was produced by the same code the tool runs, so you can check your own numbers against them.