JSONPath Tester & Query Evaluator
Test and evaluate JSONPath expressions (RFC 9535) against JSON payloads with live node highlighting
About JSONPath Tester & Query Evaluator
How JSONPath Tester & Query Evaluator Works
Tokenizes and parses JSONPath query expressions according to RFC 9535 specifications into an Abstract Syntax Tree. Recursively navigates nested JSON objects and arrays, evaluating property accessors, recursive descent (..), wildcards (*), index slices, and safe AST-based predicate filters without using eval() or Function constructors, executing 100% on-device in browser memory with zero network calls.
JSONPath Tester & Query Evaluator is an essential developer utility for testing, debugging, and validating JSONPath expressions against complex hierarchical JSON documents. Standardized under IETF RFC 9535 (and originally created by Stefan Goessner as an XPath equivalent for JSON), JSONPath is universally utilized across Kubernetes CLI queries (kubectl -o jsonpath='...'), API testing frameworks (Postman, RestAssured, Karate), AWS Step Functions, GCP Cloud Monitoring, and webhook extraction pipelines. This tool lets engineers test complex selector expressions—including recursive descent ($..), property accessors (.prop and ['prop']), array wildcards ([*]), negative indexing ([-1]), Python-style slices ([0:2]), and filter predicates ([?(@.price < 10)])—with instantaneous execution feedback, error diagnostics, and a normalized path trace view. Running 100% on-device in browser memory using a pure AST evaluator without eval(), your sensitive production JSON payloads and API responses are never transmitted over the network.
Frequently asked questions
What is JSONPath and why is it useful?+
JSONPath is a query expression language for extracting specific elements or subsets from a JSON document, much like XPath does for XML. Instead of writing custom recursive parsing loops in code, a single concise JSONPath string (e.g. $.items[*].id) can extract all target values across complex nested structures.
What is the difference between dot notation and bracket notation?+
Dot notation ($.store.book) is clean and concise for standard alphanumeric keys. Bracket notation ($['store']['book']) is required when JSON property keys contain spaces, hyphens, periods, or special characters (e.g. $['content-type'] or $['first name']).
How does recursive descent ($..) work?+
The recursive descent operator ($..) scans the entire document tree recursively at all nested depths. For example, $..author finds every 'author' key anywhere in the document, regardless of whether it is located inside an object, an array, or three levels deep.
How do filter expressions ([?(...)]) work?+
Filters test a boolean condition on each item in an array using the '@' symbol to represent the current object. For example, $.store.book[?(@.price < 10)] evaluates each book and returns only those whose 'price' property is strictly less than 10.
Is it safe to paste confidential production API payloads into this tool?+
Yes. DevToolkit Hub executes the JSONPath evaluator entirely in your browser using a pure client-side AST engine. No network requests are made, no telemetry logs your data, and no server has access to your inputs.
Limitations
Functions like count() or max() defined in some proprietary vendor extensions are not evaluated; this tool strictly implements standard RFC 9535 structural selector and filter specifications.