Paste JSON to pretty-print it, find syntax errors with line numbers, sort keys or minify it.
What is the JSON Formatter?
JSON (JavaScript Object Notation) is the most common format for APIs, config files and data exchange – but minified JSON is almost impossible to read. This JSON formatter pretty-prints your data with clean indentation, checks that it is valid and shows exactly where any syntax error is (line and column).
You can also minify JSON to make it as small as possible, sort keys alphabetically to compare two objects, and see stats like the number of keys, objects, arrays and nesting depth.
How to use the JSON Formatter
- Paste your JSON into the input box.
- Click Format (or Minify) and choose the indent size.
- Fix any error shown, then copy or download the result.
Common JSON errors
- Trailing commas – {"a":1,} is not allowed in JSON.
- Single quotes – JSON needs double quotes: "name", not 'name'.
- Unquoted keys – {name:"Ali"} must be {"name":"Ali"}.
- Comments – standard JSON does not allow // or /* */ comments.
Why format JSON?
Readable JSON makes debugging API responses much faster, helps you spot missing fields and makes code reviews easier. Minified JSON is better for production because it is smaller and loads faster.
Frequently asked questions
Is my JSON sent to a server?
No. Parsing and formatting happen entirely in your browser, so API keys and private data stay on your device.
What is the difference between format and minify?
Format adds indentation and line breaks for humans; minify removes all spaces for the smallest file size.
Can it handle large files?
Yes, several megabytes work fine in modern browsers.
Why does it say invalid JSON when my JavaScript object works?
JavaScript objects allow single quotes, comments and trailing commas; strict JSON does not.
This json formatter is 100% free, needs no signup and works on phones, tablets and computers. Your data is processed in your browser and never uploaded.
Last updated: · By NodifyTech