Kreemhunt Submit a Tool

JSON Formatter & Validator

JSON Formatter beautifies and validates JSON, highlighting syntax errors with line numbers, entirely in your browser.

No upload Instant Free No sign-up

How to format and validate JSON

  1. 1 Paste your JSON into the input box.
  2. 2 Click "Format" to beautify it, or invalid syntax is flagged with an error message.
  3. 3 Copy the formatted output.

Frequently Asked Questions

Does this upload my JSON anywhere?
No — formatting and validation happen entirely in your browser.
What does this tool do if my JSON is invalid?
It shows an error message describing what's wrong (and roughly where), based on the browser's native JSON parser error output.
Can I minify JSON instead of beautifying it?
Yes — use the "Minify" button to collapse formatted JSON back into a single compact line.

More Developer Tools

Base64 Encoder & DecoderEncode text to Base64 or decode Base64 back to text.URL Encoder & DecoderEncode or decode URL components and query strings.UUID GeneratorGenerate random UUID v4 identifiers, one or in bulk.Lorem Ipsum GeneratorGenerate placeholder Lorem Ipsum text by paragraphs, words, or sentences.Duplicate Line RemoverRemove duplicate lines from a list, keeping only unique entries.Remove Empty LinesStrip blank lines out of a block of text.Line SorterSort lines of text alphabetically, numerically, or by length.Whitespace TrimmerRemove leading, trailing, or extra inner whitespace from text.Slug GeneratorConvert any text into a clean, URL-safe slug.HTML Encoder & DecoderEscape text to safe HTML entities, or decode HTML entities back to text.CSS MinifierStrip comments and whitespace from CSS to shrink file size.JSON to CSV ConverterConvert a JSON array of objects into a downloadable CSV file.CSV to JSON ConverterConvert CSV data into a JSON array of objects.Hash Generator (SHA-1, SHA-256, SHA-512)Generate SHA-1, SHA-256, and SHA-512 hashes of any text.
Browse all Developer Tools →