Validate
JSON Validator
Wrap long lines in the input and output
JSON
Paste JSON to confirm it parses, or to mark the first syntax error.
Report
Validate
Paste JSON to confirm it parses, or to mark the first syntax error.
JSON Validator checks that pasted text is valid JSON and stops at the first syntax error. A document that parses reports its top-level type. An object also reports how many keys it has, and an array how many items, both counted only at the top level.
The check follows JavaScript JSON.parse: double-quoted keys and strings, no comments and no trailing commas. It does not pretty-print or rewrite the document, and it does not apply a JSON Schema.
Parsing runs in your browser. The text you paste is never uploaded. When the text is invalid, the problem card names the error and points at the position the parser reports so you can jump to it.
The first line reads Valid JSON. The second line names the top-level type: object, array, string, number, boolean or null. An object adds Keys with the number of top-level keys, and an array adds Items with the number of top-level items. Other types stop after the type line.
It uses JavaScript JSON.parse. Keys and strings must use double quotes. Comments, trailing commas and the bare words NaN, Infinity and undefined are rejected. Nested values are accepted when JSON.parse accepts them. Duplicate keys keep the last value, so the key count is the number of distinct keys.
The output is left empty and a problem card shows Invalid JSON. When the parser reports a character position, Jump places the caret there. When it does not, the caret stays at the start of the text. The tool does not guess a fix or rewrite the document.
No. It checks syntax only. It does not apply JSON Schema, require particular keys or compare values with a schema.
No. Validation runs in your browser and the text you paste is never uploaded, logged or stored. Google Analytics records page views and feature use, never content.
Check that XML is well-formed and point at the first error.
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Turn text into a valid JSON string literal, or decode one back to plain text.
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