Unannoy

developer

JSON Validator

Validate JSON and get a readable error before one missing comma steals the next ten minutes.

Validation result

Unexpected end of JSON input.
Validation status will appear here.

Input

0

characters

Status

Ready

browser parse

Position

-

if available

What this tool does

JSON Validator checks whether pasted JSON parses correctly and can format valid JSON for easier review.

When to use it

Use it when a config file, API response, payload, or copied snippet needs a quick sanity check before you use it elsewhere.

How it works

Paste JSON, review the valid or invalid status, and use the line or position hint when the browser parser can provide one.

Useful for

  • Check JSON snippets before putting them into config.
  • Find parse errors in copied API payloads.
  • Format valid JSON after checking that it parses.

Questions before the button mashing

Can it repair invalid JSON automatically?

No. It validates and points to the issue where possible, but deliberate edits are safer than guessing repairs.

Does JSON validation upload my payload?

No. Validation uses the browser's JSON parser, and analytics events never include the JSON text.

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