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JSON Validation

Validates JSON format, detects errors and provides fix suggestions

Input mode

1
0 Characters | 1 Lines

Validation options

Validation result

Enter JSON content to start validation

Private & SecureRuns in your browser — nothing is uploaded
Easy to UseJust paste or type — instant results
Free ForeverUnlimited use, no sign-up
Fast & ReliableAdvanced tech, fast and stable

A single missing bracket or trailing comma breaks a whole JSON file, and the error can be hard to spot by eye. Paste your JSON to check whether it is valid and, if not, see where the problem is, entirely in your browser.

valid
JSON → valid or error

How to use the JSON Validator?

  1. 1Enter inputChoose input mode (text or file) and enter/upload JSON
  2. 2Set optionsEnable options as needed: strict mode, comments, trailing commas, duplicate keys
  3. 3ProcessStart validation or rely on real-time checks; review error details and positions
  4. 4Get resultFix issues per suggestions; optional one-click formatting

Common use cases

Find a syntax errorLocate the exact spot where a stray comma or quote breaks the file.
Check before you shipConfirm a config or payload parses before you deploy it.
Debug an API bodyVerify a request or response body is well-formed JSON.
Learn the rulesSee why something you wrote is not valid JSON.

Good to know

Valid is not the same as correctA validator checks that the JSON is well-formed, not that your values make sense. Right syntax can still hold wrong data.
Strict JSON has no comments or trailing commasReal JSON forbids comments, trailing commas and single quotes, even though JavaScript allows them. That is the most common trip-up.
The error points near, not always atThe reported line is where the parser noticed the problem, which can be just after the real mistake. Look at the line above too.
It does not check a schemaValidating syntax is not the same as validating against a schema. For required fields and types, you need a schema tool.

FAQ