What is JSON?
JSON (JavaScript Object Notation) is a lightweight, text-based format for storing and exchanging structured data between applications. Despite the name, it is language-independent — human-readable for people and trivially parseable by machines, which is why it powers most modern APIs.
What does JSON stand for?
JSON stands for JavaScript Object Notation. That is the full form of the acronym: it grew out of JavaScript object literal syntax but is now a language-independent standard defined by ECMA-404 and RFC 8259.
What is a JSON file?
A JSON file is a plain-text document, usually saved with the .json extension, that holds structured data such as app settings, API responses, product catalogs or logs. Paste any sample into the online JSON viewer to explore it as an expandable tree.
What is JSON used for?
JSON is used for API request/response payloads, application and server configuration files, document storage in databases like MongoDB, structured logs, and general-purpose data exchange between virtually every programming language and platform.
What is JSON format?
The JSON format writes data as key–value pairs inside objects wrapped in curly braces { }, collections inside square brackets [ ], strings in double quotes, plus numbers, booleans and null. Run messy data through the JSON formatter to see the format applied cleanly.
What is the difference between XML and JSON?
XML wraps data in nested tags and supports attributes and namespaces, while JSON uses objects, arrays and simple types with far less markup — making it lighter to parse and a direct fit for programming-language data types. XML still suits document markup; JSON is the default for APIs. Convert either way with the XML to JSON or JSON to XML converters.
What is JSON-LD?
JSON-LD (JavaScript Object Notation for Linked Data) is a W3C standard for expressing interconnected, linked data as ordinary JSON. It is best known for embedding structured data such as schema.org markup in web pages so search engines can show rich results.
How do I open a JSON file?
Any text editor opens a .json file — Notepad, VS Code, Sublime Text — and web browsers can display the raw contents too. For large or deeply nested files, upload or paste it into the online JSON viewer, or run it through the formatter first to make it readable.
How do I read a JSON file?
Reading JSON means parsing its structure: objects become key–value pairs, arrays become ordered lists. Humans can read formatted JSON directly, while code reads it with parsers like JSON.parse() in JavaScript or json.load() in Python. The tree-style JSON viewer lets you browse any file without writing code.
How do I create a JSON file?
Write your data following JSON syntax rules in any text editor and save it with a .json extension, for example config.json. The easiest route: build it in the online JSON editor — live validation guarantees correct syntax — then copy or download the finished file.
How do you comment in JSON?
You cannot — the JSON specification has no comment syntax, which is why tools reject // or /* */. Common workarounds: keep notes in a separate README, use a custom "_comment" key, or use supersets like JSON5/JSONC if your tooling accepts them.
How do I format JSON online?
Paste your JSON into the input area on this page and the formatter beautifies it instantly with your choice of 2, 3 or 4-space indentation. You can also minify, sort keys and copy or download the result.
Is this JSON formatter free and private?
Yes. Jsonr is completely free with no signup. All formatting, validation, comparison and conversion runs locally in your browser, so no data ever leaves your device.
How can I compare two JSON files?
Switch to Compare mode, paste both JSON documents, and Jsonr highlights added, removed and changed values side by side, with a summary of all differences.