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JSON Formatter & Validator

Beautify, minify, and validate JSON data with syntax highlighting

Input JSON

Output

How JSON Formatting Works

JSON (JavaScript Object Notation) is a lightweight data interchange format. This tool helps you format, validate, and explore JSON data.

Features

Frequently Asked Questions

What is JSON formatting?
JSON formatting (or beautifying) adds proper indentation and line breaks to compressed JSON data, making it human-readable while keeping the data structure intact.
How do I validate JSON?
Paste your JSON into the input field and click Validate. The tool will check for syntax errors like missing commas, brackets, or quotes and show the exact error position.
What is the difference between Format and Minify?
Format (beautify) adds indentation and newlines for readability. Minify removes all unnecessary whitespace to reduce file size, ideal for production use.
Can I view JSON as a tree?
Yes, toggle the Tree View to see your JSON data as a collapsible, hierarchical tree structure for easy navigation of nested objects and arrays.

Related Tools

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What is a JSON formatter?

A JSON formatter re-indents raw JSON into readable, nested form, validates the syntax, and reports the exact line and character where invalid JSON breaks.

SnoopTool's formatter parses and pretty-prints in the browser, so API responses containing keys or customer data are never uploaded. It can also minify JSON back to a single line for transport.

JSON Formatter: key facts

Reference facts for the SnoopTool JSON Formatter, a free browser-based tool.
OperationsBeautify (indent), minify, validate, tree view
ValidationReports the position of the first syntax error
Common errors caughtTrailing commas, single quotes, unquoted keys, NaN/undefined
PrivacyParsing happens client-side; payloads are not uploaded
CostFree, no size cap for typical API responses

Why use the SnoopTool JSON Formatter?

How to use the JSON Formatter (step by step)

  1. Paste your JSON. Drop the raw or minified JSON into the input pane.
  2. Click Format. The formatter validates and re-indents the document.
  3. Fix any errors. If the JSON is invalid, the message names the line and character to correct.
  4. Copy the result. Copy the beautified output, or press Minify for a compact single line.

Related free tools on SnoopTool

XML to JSONJSON to CSVJSON to ExcelJWT DecoderHTML Beautifier

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