Instantly check if your JSON is valid — with exact line & column error location, fix hints, and full structure analysis.
Paste your JSON — validation starts automatically as you type.
If invalid, the exact line, column, and a helpful fix hint are shown.
Valid JSON shows key count, depth, type info, and size stats.
{"name":"Alice",} ← remove the comma before }
JSON does not allow trailing commas after the last item in an object or array.
{'name':'Alice'} ← use double quotes "name":"Alice"
JSON requires double quotes for both keys and string values. Single quotes are not valid.
{name:"Alice"} ← use "name":"Alice"
Object keys must always be quoted strings in JSON (unlike JavaScript objects).
{"name":"Alice" // this is wrong} ← remove comments
JSON does not support comments (// or /* */). Remove them before validating.
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Yes. All validation uses JavaScript's built-in JSON.parse() and runs entirely in your browser. Nothing is sent to any server.
This usually means a character that isn't valid in JSON was found — like a single quote, a trailing comma, or an unquoted key. The validator shows you the exact position to help you find it quickly.
Depth is the maximum number of nested levels in your JSON. A flat object has depth 1. A deeply nested structure like {"a":{"b":{"c":1}}} has depth 3.