JSON Formatter & JSONPath

No. Formatting, validation and JSONPath evaluation all run in your browser with JavaScript — nothing you paste here is sent to our servers or anyone else's. You can verify this in your browser's network tab: no requests fire when you format or query.

JSONPath is a query language for JSON, analogous to XPath for XML. $ is the document root, dots and brackets navigate into it: $.checks[0].name takes the name of the first item in the checks array. Wildcards ($.checks[*].name) and recursive descent ($..name — any depth) let one expression pull values from anywhere in the document. It's the standard way monitoring tools, API tests and low-code platforms reference response fields.

Root ($), dot and bracket children ($.a, $['a b']), array indexes including negative ($[0], $[-1]), slices ($[1:3]), wildcards ($.* and $[*]) and recursive descent ($..price, $..*). Filter expressions like $[?(@.price > 10)] are not supported — implementations disagree wildly on their semantics, so we'd rather not pretend.

The usual suspects: forgetting the $ root ($status instead of $.status); using a dot for a key that contains spaces or dashes (use $['content-type'] instead of $.content-type); querying an array without an index or wildcard ($.checks.name instead of $.checks[*].name); or case differences — JSON keys are case-sensitive.

Paste the document and the validator reports the line and column of the first character it couldn't parse. The most common errors are trailing commas after the last item, single quotes instead of double quotes, unquoted keys, and comments — none of which strict JSON allows (they're JSON5/JSONC extensions).

Strict JSON (RFC 8259) allows neither. Trailing commas, comments, single quotes and unquoted keys come from looser dialects — JSON5, JSONC (what VS Code settings use), or plain JavaScript object literals. If a config file needs comments, the file format has to explicitly support JSONC; an API returning them is broken.

JSONPath is a compact query language for selecting values; jq is a full transformation language with pipes, functions, arithmetic and restructuring. For "give me this field" — JSONPath. For "reshape this document into another" — jq. API monitoring assertions almost always need the former: select a value, compare it against an expectation.