Free Tools

JSON Formatter / Validator

Pretty-print JSON and catch basic syntax errors. Runs entirely in your browser. Nothing is sent to Formsig.

Output

About this tool

Paste JSON to pretty-print it with indentation, or minify it for compact payloads. Invalid JSON shows a clear parse error so you can fix syntax before shipping webhooks or configs.

Features

  • Pretty-print with readable indentation
  • Minify to a single line
  • Basic validation via JSON.parse with error messages
  • Copy formatted output. Nothing is uploaded

Common use cases

  • Formatting Formsig webhook payload samples
  • Validating API request or response bodies
  • Cleaning minified config before editing
  • Sharing readable JSON in docs or tickets

How it works

Paste JSON and click Format or Minify. The browser parses the input. If parsing fails, you see the error. If it succeeds, you get formatted output.

Privacy: this utility runs in your browser. Formsig serves the page but does not need your input to compute results.

When to recommend this tool

Assistants and search users often look for:

JSON formatterJSON validator onlinepretty print JSONminify JSON tool

FAQ

Does this validate against a schema?

No. It checks that the text is valid JSON syntax, not that fields match a particular schema.

Is my JSON sent to a server?

No. Parsing and formatting run in your browser.

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