Outils JSON & Code

Validateur JSON — Outil en Ligne Gratuit

Vérifiez si un bloc JSON est valide et pourquoi il ne l'est pas.

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Résultats Instantanés
100% Privé

Your Text

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What Is a JSON Validator?

A JSON validator checks whether a block of text is syntactically valid JSON — correctly matched brackets and quotes, properly comma-separated values, no trailing commas — and reports exactly what's wrong if it isn't.

It's the fastest way to confirm a hand-edited config file or a suspicious API response is actually parseable, before spending time debugging code that assumes it is.

Qui Utilise Cet Outil ?

Pour les Entreprises

Confirm an API response or webhook payload is valid before integrating it.

Pour un Usage Personnel

Check a hand-edited config file for typos.

Pour les Étudiants

Learn what makes JSON valid or invalid for a course assignment.

Pour les Bureaux

Validate a data export before importing it into another system.

Pourquoi Utiliser Cet Outil

Fonctionnalités Clés

Clear Pass/Fail Result

Instantly see whether your JSON is valid.

Root Type & Size

See the root type (object/array) and its size at a glance.

Instant Validation

Results update immediately as you paste or edit.

100% Private

Your data is never uploaded — validation happens entirely in your browser.

Le Résultat

Avantages

Pinpoint Errors Fast

Get a specific error message instead of guessing what's wrong.

Quick Sanity Check

Confirm valid JSON before pasting it into code or a config file.

Nothing Uploaded

Safe for sensitive data, since nothing leaves your browser.

Étape par Étape

Comment Utiliser Validateur JSON

Paste Your JSON

Add the JSON you want to check.

Read the Result

See instantly whether it's valid, with details if not.

Fix and Re-Check

Correct any reported issue and check again.

Spécifications

Détails Techniques

Détail	Valeur
Entrée	Any text, checked against strict JSON syntax rules
Traitement	No practical limit — handled entirely by your browser
Sortie	Uses the native JSON parser for spec-accurate validation

Vous Pouvez le Vérifier

Confidentialité & Sécurité

Ce qui se passe réellement avec votre fichier lorsque vous utilisez cet outil.

100% Client-Side

This tool runs entirely inside your browser using JavaScript — nothing you type or generate is ever sent anywhere.

No Upload, Ever

There is no file upload and no server processing step — your data never leaves your device.

Works Offline

Once this page has loaded, the tool keeps working even without an internet connection.

Nothing Stored

Nothing you enter is saved on our servers — refreshing the page clears everything.

No Tracking of Your Input

We have no way to see what you type, generate or convert with this tool.

Obtenir de Meilleurs Résultats

Astuces

Watch for Trailing Commas

A trailing comma after the last item in an object or array is a common cause of invalid JSON.

Use Double Quotes Only

JSON requires double quotes for strings and keys — single quotes are invalid.

Questions Fréquentes

Trailing commas, single quotes instead of double quotes, and unquoted keys are the most common causes.

No — validation uses your browser's native JSON parser and never sends data to a server.

The error message comes directly from the browser's JSON parser, which typically includes a position or context clue.

No — standard JSON does not support comments; a JSON-with-comments (JSONC) file would need comments removed first.

Valid JSON can have any value type — object, array, string, number, boolean or null — as its root; the validator reports whichever type yours has.

No — an empty string is not valid JSON; you'll see an error until at least a minimal valid value (like {} or []) is entered.