Technology & Integrations

JSON

A text format for exchanging data between systems, written in key-value pairs and adopted as the standard by most web APIs.

Also known as: what is json · json file · json format · json example

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JSON (JavaScript Object Notation) is a text format for exchanging data between systems, written in key and value pairs. It is what practically every modern API returns and what almost every webhook delivers to your door.

The structure

{
  "event": "message_received",
  "contact": {
    "name": "Ana Souza",
    "phone": "5531999998888"
  },
  "tags": ["hot lead", "instagram"],
  "replied": false
}

Curly braces {} hold objects; square brackets [] hold lists; text goes in double quotes; numbers, true, false and null go with no quotes. Objects can contain other objects — that nesting ability is what CSV does not have.

JSON or CSV

	JSON	CSV
Structure	nested, hierarchical	flat table
Types	text, number, boolean, null	everything is text
Human readability	reasonable	good
Typical use	API, webhook, configuration	importing and exporting lists

A contact with three phone numbers and five tags fits naturally into JSON; in CSV, it becomes a repeated column or a field with a separator inside the field.

The mistakes that break a JSON file

A trailing comma before closing a brace or bracket, single quotes instead of double, a comment (JSON does not allow those), and an unquoted key. One wrong character invalidates the entire file — there is no "half a JSON." Before opening a support ticket with a vendor, paste the content into a validator.

Valid JSON does not mean correct data

The format guarantees syntax, not content. A phone number missing the country code, a date in a local format where ISO 8601 was expected (2026-08-01T14:30:00Z), and a missing required field all pass JSON validation and break the integration. What defines "valid" is the API's documentation, not the format's parser.

Frequently asked questions

What is a JSON file?

It is a text file that organizes data in key-value pairs, readable by both people and machines. It allows nested structures, like a contact that contains a list of tags inside it. It is the most used format today for exchanging data between systems.

What is JSON used for?

It is used for two systems to exchange data with a defined structure: an API's response, a webhook's body, a configuration file. It won out because it is simple to read, light to transfer, and supported by every programming language. Anyone integrating systems lives with JSON daily.

How do I open a JSON file?

Any text editor opens it, including Notepad. To read it comfortably, use a viewer that formats and collapses blocks, like a code editor or a browser extension. Avoid opening it in Word, which can insert characters and corrupt the file.

What is the difference between JSON and XML?

Both represent structured data, but XML uses opening and closing tags and takes up much more space. JSON is leaner and more direct to convert into an object in most languages. New APIs are born in JSON; XML survives in older systems and tax integrations.

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