Developer tools / JSON

JSON Formatter & Validator

Clean up messy JSON, catch syntax errors, and explore nested data without sending anything to a server.

Indent
InputJSON
{
  "project": "Practical Tool Lab",
  "active": true,
  "tools": [
    "JSON Formatter",
    "Timestamp Converter"
  ],
  "owner": {
    "name": "Xiao & Mei",
    "location": "Shanghai"
  }
}
Valid JSON
180 B6 keys6 valuesDepth 2Processed locally

Pinpoint errors

See a clear validation message with the exact line and column whenever possible.

Explore as a tree

Collapse deeply nested objects and arrays instead of scanning hundreds of lines.

Private by design

Formatting happens locally in your browser. Your JSON is never uploaded to us.

How to format JSON

  1. 1. Add your data. Paste JSON into the input editor or drop a .json file.
  2. 2. Fix any errors. The validator shows where parsing stopped so you can correct the source quickly.
  3. 3. Use the result. Format, minify, sort keys, inspect the tree, then copy or download the cleaned JSON.