JSONata Tester
Run JSONata expressions against JSON documents in your browser with instant results and error feedback.
Test JSONata queries against live JSON
JSONata is a lightweight query and transformation language for JSON. Paste a document, write an expression, and see the evaluated result instantly in your browser. Pair it with Extract JSON Values when you need flat lists from nested trees.
Common JSONata patterns
- Filter arrays with predicates such as
items[price > 10]. - Project fields using object literals like
{ name: title, cost: price }. - Aggregate with functions such as
sum(),max(), andcount().
Frequently Asked Questions
Is my JSON uploaded to a server?
No. Parsing and evaluation run entirely in your browser.
Which JSONata version is supported?
The tool uses the jsonata npm package bundled with the site, which tracks the public JSONata specification.
Why do I see undefined?
JSONata returns undefined when a path does not match any value. The tool prints the string undefined so you can spot empty results.
Can I format strings or dates?
Yes. JSONata includes string and date helpers. Check the official JSONata documentation for function names and examples.
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