Instant validation
Validates JSON syntax in real time as you type, with a descriptive error including line and column.
What is JSON?
JSON (JavaScript Object Notation) is the standard format for exchanging data between web applications. REST APIs, config files and NoSQL databases all use JSON. A syntax error — a trailing comma, the wrong quotes — can break the whole app. This validator spots the issue instantly and shows exactly where it is.
Validator features
Pretty print
Turns compact JSON into a readable format with 2-space indentation.
Minify
Strips spaces and line breaks to produce the most compact JSON possible.
Tree view
Inspect the structure as a navigable tree, with types, values and collapsible nodes.
100% in the browser
No data is sent to servers. All processing happens on your device.
Free, no sign-up
Use it as much as you want, with no account and no usage limits.