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Validate a JSON API Response
Check whether an API response is valid JSON before debugging the client, schema, or integration code.
Problem
An API response looks correct in the browser or terminal, but the client cannot parse it.
What to do
Before changing application code, confirm the response is valid JSON. A single unescaped character, HTML error page, or trailing comma can make a response unusable.
- 1Copy the raw response body.
- 2Validate it as JSON and inspect the first reported error.
- 3Format the valid response so nested fields are easier to review.
Use the browser tool
JSON Validator checks JSON syntax and reports the exact line and reason for any error in plain English, so you can fix malformed payloads fast. It runs as you type, entirely in your browser, making it safe for private or production data.
People also ask
- How do I use JSON Validator?
- Paste or drop your data into the workspace, adjust the options to fit your data, then copy or download the result. Validate JSON syntax with helpful error messages.
- Is my data uploaded or stored anywhere?
- No. Everything runs locally in your browser — your data is never uploaded to a server. Nothing is sent to a server, so it's safe to use with private or sensitive data.
- Is JSON Validator free?
- Yes — it's completely free with no account, no sign-up, no watermark, and no daily usage limits.