JSON Validator

Validate JSON syntax online

This JSON validator checks whether the input can be parsed as a JSON document. Valid input produces a success result; invalid input reports the parsing error so you can locate problems such as missing delimiters, incorrectly quoted strings, or unsupported values.

Validation here checks JSON syntax. It does not check whether an object contains the fields, types, or business rules required by a particular API, and it does not validate against a JSON Schema.

How to check JSON

1. Paste the complete JSON document into the input editor.
2. Click Validate.
3. If an error is shown, inspect the reported token or position and the characters immediately before it.
4. Correct the input and validate again until it succeeds.

When debugging a long document, also check that every { has a matching }, every [ has a matching ], object members are separated by commas, and property names use double quotes.

What counts as valid JSON?

According to RFC 8259, a JSON value may be an object, array, number, string, true, false, or null. Standard JSON does not support comments, NaN, Infinity, undefined, hexadecimal numbers, or trailing commas.

A syntactically valid document is not necessarily safe, correct, or suitable for your application. Consumers may impose limits on nesting, number ranges, text length, duplicate property names, or accepted fields.

JSON validator FAQ

Why is a valid JavaScript object rejected?

JavaScript object literal syntax is broader than JSON. Replace single quotes with correctly escaped double-quoted strings, quote property names, remove comments and trailing commas, and replace JavaScript-specific values.

Does validation modify my JSON?

No. The validator reports whether parsing succeeds and leaves the input unchanged. Use the JSON Formatter for readable indentation or the JSON Minifier for compact output.

Does this validate a JSON Schema?

No. Syntax validation answers whether the document is JSON; schema validation additionally checks the document’s structure and constraints against a separate schema.