What happens if my JSON is invalid?

You'll see a clear error message describing the problem instead of a formatted result.

Is my JSON data uploaded anywhere?

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

Does formatting change the actual data?

No — only whitespace and indentation change; keys, values and structure remain identical.

Can I use a custom indent size?

Yes — choose any indent size from 1 to 8 spaces.

Does this support very large JSON files?

Yes, limited only by your browser's available memory.

What is the difference between this and the JSON Beautifier?

They work almost identically; the Beautifier additionally offers a tab-indent option alongside numeric space counts.

Outils JSON & Code

Formateur JSON — Outil en Ligne Gratuit

Formatez et indentez du JSON désordonné en une structure lisible.

Utiliser Cet Outil

Fonctionne dans Votre Navigateur
Résultats Instantanés
100% Privé

Your Text

Indent size

What Is a JSON Formatter?

A JSON formatter takes minified or inconsistently indented JSON and rewrites it with clean, consistent indentation, making nested objects and arrays easy to read and debug at a glance.

This is especially useful when working with API responses, which are almost always returned minified to save bandwidth — pasting one into a formatter instantly reveals its structure without needing to trace matching brackets by eye.

Qui Utilise Cet Outil ?

Pour les Entreprises

Inspect a minified API response to understand its structure.

Pour un Usage Personnel

Read a configuration file that was saved without formatting.

Pour les Étudiants

Learn JSON structure for a web development or API course.

Pour les Bureaux

Format a data export for easier manual review.

Pourquoi Utiliser Cet Outil

Fonctionnalités Clés

Custom Indent Size

Choose an indent size from 1 to 8 spaces.

Instant Formatting

Output updates immediately as you paste in JSON.

Clear Error Messages

Invalid JSON shows exactly what went wrong.

100% Private

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

Le Résultat

Avantages

Instantly Readable

Turn a wall of minified JSON into a clearly indented structure.

Faster Debugging

Spot missing brackets or misplaced values much more easily once formatted.

Nothing Uploaded

Safe for sensitive API payloads, since nothing leaves your browser.

Étape par Étape

Comment Utiliser Formateur JSON

Paste Your JSON

Add minified or messy JSON into the input box.

Choose an Indent Size

Pick how many spaces to indent each level.

Copy the Formatted Result

Use the Copy or Download button to grab the result.

Spécifications

Détails Techniques

Détail	Valeur
Entrée	Valid JSON text
Traitement	No practical limit — handled entirely by your browser
Sortie	Exact, lossless re-formatting using the native JSON parser

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

Use 2 Spaces for Web Projects

2-space indentation is the most common convention for JSON in web projects.

Check the Validator First on Large Payloads

If formatting fails, use the JSON Validator to pinpoint the exact error.

Questions Fréquentes