JoliTools

JSON Validator

Validate JSON with friendly error messages

Result
Validation result appears here…

Valid JSON is pretty-printed on success so you can inspect it. Parsing happens locally in your browser. API keys and private data in your JSON are never uploaded.

About this tool

A single misplaced comma can break an entire API call, and raw parser errors like Unexpected token are famously unhelpful. This validator translates them into plain English.

Paste your JSON and get an instant verdict: valid, or a clear explanation of the exact problem and where to look. The fastest way to debug config files and API payloads.

How to use the json validator

  1. 1Paste your JSON.
  2. 2Click Validate.
  3. 3See valid confirmation or a clear error explanation.
  4. 4Fix and re-validate instantly.

Frequently asked questions

Trailing commas, missing quotes, unclosed brackets, single quotes, and anything else that breaks strict JSON, each explained in plain language.

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