How do I use the JSON formatter and validator?
- Paste your JSON into the input box, or load the example.
- Choose Format to indent it, or Minify to remove whitespace.
- If the JSON is invalid, fix the line and column shown in the error.
- Copy or download the result.
What are the most common JSON errors?
| Error | Example | Fix | |
|---|---|---|
| Trailing comma | {"a": 1,} | Remove the last comma | |
| Single quotes | {'a': 1} | Use double quotes | |
| Unquoted key | {a: 1} | Quote every key | |
| Comments | {"a": 1 // note} | Remove comments | |
| Missing bracket | {"a": [1, 2} | Close every bracket | |
When do developers use a JSON formatter?
Reading API responses while debugging an integration, checking webhook payloads from WhatsApp, payment gateways or CRMs, editing configuration files, preparing test data and reviewing structured data before publishing. Formatting makes the structure visible, and validation catches the small syntax mistakes that break builds and integrations.
JSON formatter and validator: frequently asked questions
Is my JSON sent to your server?
No. Formatting and validation run entirely in your browser.
What makes JSON invalid?
The usual causes are single quotes, a trailing comma after the last item, comments, and unescaped line breaks inside strings.
What does a JSON formatter do?
It adds consistent indentation and line breaks to JSON so it is easy to read, and checks that the JSON is valid.
Why is my JSON invalid?
The usual causes are trailing commas, single quotes instead of double quotes, unquoted keys, comments, or a missing bracket. The error message shows the line and position.
Can I minify JSON as well?
Yes. Minifying removes all whitespace to make the payload smaller for APIs and storage.
Is there a size limit?
Formatting runs in your browser, so the practical limit is your device’s memory; files of several megabytes work fine.
Does it sort keys?
Keys keep their original order so the output matches what your API returned.
Can it handle JSON with Arabic text?
Yes. JSON is Unicode, and Arabic or emoji characters are preserved exactly.
What indentation should I use?
Two spaces is the most common convention in JavaScript projects; four spaces is common in Python projects.
Is it safe to paste API responses with tokens?
The formatter never sends data anywhere, but treat tokens as secrets and rotate any you have shared elsewhere.