JSON Formatter and Validator
Validate, format, minify, and organize JSON data instantly without uploading it.
JSON input
Formatted JSON
Enter JSON to begin
Validated and formatted output will appear here automatically.
JSON validation
Find malformed JSON before using it
Invalid JSON can cause failed API requests, configuration errors, parsing failures, and application crashes.
Strict JSON syntax
JSON requires double-quoted property names and strings. It does not allow comments, trailing commas, undefined values, or JavaScript expressions.
Safe local processing
Formatting is performed locally, making the tool suitable for API responses, configuration files, logs, and other development data.
Guide
About JSON Formatter and Validator
JSON is a widely used text format for APIs, configuration, logs, cloud services, and web applications.
This tool validates JSON syntax, formats documents, minifies output, sorts object keys, and reports structural statistics.
Processing is performed locally so the input does not need to be uploaded.
Formatting and validation
Valid JSON can be pretty-printed or minified without changing its data model.
Common JSON errors
Most parsing problems come from punctuation or string syntax.
- Missing commas
- Trailing commas
- Single-quoted strings
- Unescaped quotation marks
- Comments
- Unmatched braces or brackets
Sorting object keys
Alphabetical key ordering can improve deterministic comparisons, but JSON object order should not carry application meaning.
Privacy and sensitive data
Avoid placing production secrets in unnecessary tools, logs, URLs, or analytics even when processing is local.
FAQ
Frequently asked questions
Does formatting change JSON data?
No. It changes whitespace and presentation only.
Why are single quotes invalid?
The JSON grammar requires double quotation marks for strings and property names.
Can JSON contain comments?
Standard JSON does not support comments.
What is minified JSON?
It is valid JSON with unnecessary whitespace removed.
Are duplicate keys safe?
They should be avoided because parser behavior can differ.
Is my JSON uploaded?
Formatting and validation are intended to run locally in your browser.
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