À propos des fichiers JSON

Q: Comment ouvrir et convertir un fichier JSON en ligne ?

Importez simplement votre fichier JSON dans KaijuConverter pour le convertir en PDF, JPG, PNG ou tout autre format standard sans installer de logiciel.

Q: La conversion de fichiers JSON est-elle gratuite et sécurisée ?

Oui, la conversion est gratuite jusqu'à 25 Mo (et jusqu'à 1 Go avec le Pass 24h ou Pro). Tous les fichiers sont chiffrés via TLS 1.3 et supprimés automatiquement après 60 minutes.

JSON (JSON Data · Format de document)

Lancement 2001 Par Douglas Crockford

JSON Data (.json) est un format de fichier pris en charge par KaijuConverter pour l’archivage, l’échange professionnel et la conversion multiplateforme.

Famille

Documents & Text

Extension

.json

Type MIME

application/json

Utilisable comme

Entrée Sortie

L'histoire

COMMENT JSON
A VU LE JOUR.

2001

2002

2013

2017

JSON — JavaScript Object Notation — was popularized by Douglas Crockford around 2001-2002 as a lightweight alternative to XML for browser-server data exchange. The syntax was lifted directly from the way JavaScript already defined object literals, which made parsing trivially cheap in the browser: eval(jsonString) worked (before anyone realized that was a security nightmare).

JSON went from a hack to a standard remarkably fast: ECMA-404 in 2013, RFC 8259 in 2017, and by then nearly every new REST API used it instead of XML. Crockford’s famous line was "I don’t want to maintain JSON" — he refused to version the format, arguing simplicity was its main virtue. Today JSON carries config files, API payloads, logs, database documents, build manifests, and an ever-growing chunk of the data plumbing of the internet.

CURIOSITÉS ET
ANECDOTES.

JSON is a subset of JavaScript, but not a strict one — some valid JSON (like leading zeros) is invalid JS, and vice versa.

Douglas Crockford intentionally refused to version the format: "JSON is done. It does not need a v2."

JSON does not permit trailing commas or comments — which is why JSONC (JSON with Comments) and JSON5 were invented.

The largest public JSON file is OpenStreetMap's planet dump — over 100 GB minified.

JSON's only allowed whitespace outside strings is tab, space, newline, and carriage return — nothing else.

POINTS FORTS ET
LIMITES.

Points forts

Dead-simple — you can memorize the entire grammar on one page.
Native parsers in every programming language.
Human-readable and easy to debug.
Compact — much smaller than equivalent XML.
Frozen spec — a JSON parser written in 2010 still handles new JSON files from 2026.

Limites

No comments allowed — config files feel verbose.
No trailing commas — a constant source of parse errors.
No native date, decimal, or binary types — everything is strings or numbers.
Easily bloated by repeated keys; large payloads compress poorly vs binary alternatives.
Streaming is awkward — JSON wants to be parsed whole.

Tailles et poids typiques

Small config

< 1 KB

REST API payload

1-100 KB

Database export

10 MB - 100 GB

Spécifications techniques

MIME type: application/json
Extension: .json
Standard: ECMA-404, RFC 8259
Encoding: UTF-8, UTF-16, or UTF-32
Allowed types: object, array, string, number, boolean, null

CONVERTIR DEPUIS
JSON

json pdf json docx json odt json txt json md json html json tsv json epub json rst

CONVERTIR EN
JSON

xls json xlsx json ods json csv json tsv json txt json

Cas d'usage courants

Web APIs, configuration files, data exchange, NoSQL databases