Reference
What is JSON? A plain-language reference for the JSON data interchange format, its grammar, and its limits.
G By Gampangin · Published July 1, 2026 · Updated September 27, 2026 · Reviewed by Gampangin · 1 min read · JSON AI-assisted draft. Editorial responsibility: Gampangin .
JSON is a text format for structured data built from objects, arrays, strings, numbers, booleans, and null. RFC 8259 defines the grammar; it does not define a schema.
01 What JSON is notJSON is not a schema language and not a substitute for application validation. Two documents can both be valid JSON and still disagree about fields and types.
02 LimitationsLimitations
This reference covers the JSON grammar only. It says nothing about the meaning, schema, or safety of the data you parse.
Frequently asked questions Is JSON the same as JavaScript objects? No. JSON is a stricter text grammar; it disallows trailing commas, comments, and unquoted keys that JavaScript object literals may allow. About the author Gampangin — Publisher and editorial team
Gampangin builds and maintains free, browser-based developer tools and the documentation that makes them trustworthy. The organization is accountable for every page published on this site.
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