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JSONPath Cheat Sheet: Query Any JSON Document

June 27, 20266 min read

JSONPath is a query language for JSON, analogous to XPath for XML. Given a deeply nested JSON document, a JSONPath expression lets you extract one value, a list of values, or everything that matches a pattern — without writing loops. It is supported natively in PostgreSQL (jsonb_path_query), AWS CloudFormation, Kubernetes admission webhooks, and most API testing tools.

Root and current node

Symbol	Meaning
`$`	Root of the document
`@`	Current node (used inside filter expressions)

Every JSONPath expression starts with $.

Navigation operators

Operator	Meaning	Example
`.key`	Child key (dot notation)	`$.user.name`
`["key"]`	Child key (bracket notation — use for keys with spaces or special chars)	`$["first name"]`
`[n]`	Array element at index n (0-based)	`$.items[0]`
`[*]`	All array elements (wildcard)	`$.items[*].id`
`.*`	All children of current node	`$.user.*`
`..`	Recursive descent — searches all depths	`$..name`

Array slicing

JSONPath supports Python-style slice notation [start:end:step]:

Expression	Result
`$.a[0:3]`	Elements at index 0, 1, 2
`$.a[-1]`	Last element
`$.a[::2]`	Every second element (0, 2, 4 …)
`$.a[1,3]`	Elements at index 1 and 3 (union)

Filter expressions

Filter expressions use ?(…) syntax to select elements that satisfy a condition. Inside the filter, @ refers to the current array element:

Expression	Selects
`$.items[?(@.price < 10)]`	Items where price is less than 10
`$.users[?(@.active == true)]`	Active users
`$..book[?(@.isbn)]`	Any book with an isbn field
`$.orders[?(@.total >= 100 && @.status == "shipped")]`	Shipped orders over $100

Practical examples

Given this document:

{
  "store": {
    "books": [
      { "title": "Clean Code",    "price": 29.99, "inStock": true  },
      { "title": "Refactoring",   "price": 34.99, "inStock": false },
      { "title": "The Pragmatic Programmer", "price": 39.99, "inStock": true }
    ]
  }
}

Expression	Result
`$.store.books[*].title`	All three titles
`$.store.books[-1].title`	`"The Pragmatic Programmer"`
`$.store.books[?(@.inStock)].title`	`"Clean Code"`, `"The Pragmatic Programmer"`
`$.store.books[?(@.price < 35)].title`	`"Clean Code"`, `"Refactoring"`
`$..price`	All three prices (recursive)

JSONPath in JavaScript

No native browser or Node.js API supports JSONPath — you need a library. The most widely used is jsonpath-plus:

import { JSONPath } from "jsonpath-plus";

const result = JSONPath({
  path: "$.store.books[?(@.price < 35)].title",
  json: document,
});
// ["Clean Code", "Refactoring"]

JSONPath in PostgreSQL

PostgreSQL 12+ supports the SQL/JSON standard path language (similar to JSONPath) via jsonb_path_query:

SELECT jsonb_path_query(data, '$.store.books[*] ? (@.price < 35).title')
FROM products;

Gotchas

No universal standard — RFC 9535 (2024) finally standardised JSONPath, but many tools pre-date it and differ in filter syntax and recursion behaviour. Test your expressions against your specific library.
Recursive descent is slow on large documents — $..key traverses the entire tree. Use specific paths in performance-sensitive code.
Missing nodes return an empty array, not null — account for this in your error handling.

Try it yourself

Use the free browser-based JSON Formatter & Validator on DevBench — no signup, runs entirely in your browser.

Open JSON Formatter & Validator