Online JSON Formatter and Validator
Paste JSON of any size — the tool instantly formats it with proper indentation and highlights errors. Minify it back with a single click.
Frequently asked questions
How do I format JSON online?
Paste your JSON into the input field and click "Format" — the tool will add proper indentation and line breaks. If there are errors in the JSON, they will be highlighted with the line number indicated.
What is JSON minification?
Minification removes whitespace and line breaks from JSON to reduce its size. It is used before transmitting data over the network: minified JSON takes up 20–40% less space.
Why won't my JSON parse — common errors?
Common mistakes include: single quotes instead of double quotes, a trailing comma after the last element, unclosed brackets, and numbers wrapped in quotes when numeric values are expected.
Is it safe to paste data into an online formatter?
Yes — the tool runs entirely in the browser (client-side JavaScript). Your data is never sent to a server and is not stored anywhere.
Need a full SEO audit?
Tools help with targeted tasks. For systematic growth — request a free review of your site.