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JSON validator

Check JSON syntax, inspect value types and nesting depth, and save a clear local validation report.

Source
174 / 1,000,000 charactersLocal only
Live validation
Valid JSON

Your document is valid within this tool’s limits.

11Values
2Deepest level
objectRoot type
object2
array1
null1
string5
number1
boolean1
Processed on your device

How it works & useful details

How it works

Check strict JSON syntax without changing your document. Comments, trailing commas, single-quoted strings and unquoted keys are not JSON. This checks syntax and supported size/number limits; it does not validate against a JSON Schema.

Limits & privacy

Up to 1,000,000 characters, 50,000 values and 64 levels. Live previews pause above 40,000 characters; run the tool to process the full supported input. Imported files must be UTF-8 and under 1 MB. Your data stays on this device.

Numbers use JavaScript decimal precision. Unsupported large integers are rejected; quote identifiers to keep all digits. Duplicate object names keep their last value. Transforms preserve data, not source whitespace or number spelling.

Paths use JSON Pointer: an empty path selects the root, ~0 escapes a tilde, and ~1 escapes a slash.