JSON Validator
Validate JSON instantly with precise error line and column. Catch missing commas, unquoted keys, trailing commas and bad escapes before they break your app.
This tool runs entirely in your browser. Your data never leaves your device — it is not uploaded to any server.
How to use
- 1Paste your JSON into the input box.
- 2A green status appears if the JSON is valid; otherwise the exact line, column and reason are shown.
- 3Fix the reported position, or copy the pretty-printed output when validation passes.
JSON Validator
Paste any JSON document and see at a glance whether it is valid. The validator is strict: it follows the JSON standard, so common mistakes like single quotes, trailing commas, unquoted keys and comments are all reported.
When something is wrong you get the exact line and column plus a human-readable reason — not a cryptic one-line message. Valid input is rewarded with a pretty-printed version you can copy straight away.
Frequently asked questions
Which errors can the validator find?
All standard JSON syntax errors: missing or extra commas, unquoted or single-quoted keys, trailing commas, unescaped control characters, invalid escapes, and stray content after the value — each reported with line and column.
Does it also check the schema or just the syntax?
Syntax only. It verifies the document is valid JSON, not that fields have expected types or values — for that you need a schema validator such as JSON Schema.
Is my JSON uploaded anywhere?
No. Validation happens locally in your browser; nothing leaves your device.
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Embed this tool
Put this tool on your own site with one line — it runs entirely in the visitor's browser.
<iframe src="https://zoyku.com/en/tools/json-validator?embed=1" width="100%" height="640" style="border:0;border-radius:16px" title="Zoyku — json-validator" loading="lazy"></iframe>