JSON Formatter – Secure & 100% Client-Side
Your data privacy is our top priority. Unlike other tools that upload your files to a server, JSON Formatter Pro processes everything locally in your browser (Client-Side). This means your sensitive API keys, customer data, and proprietary code never leave your device. It is the perfect secure solution for developers working with confidential JSON blocks.
JSON Formatter Pro is a fast, secure JSON formatter that runs entirely in your browser.
Supports fixing common JSON errors like trailing commas and single quotes.
Handles Large JSON Files Smoothly
Struggling with massive log files or API dumps? Most online formatters crash with big datasets. Our large file JSON formatter uses the high-performance Monaco Editor engine to handle files up to 10MB effortlessly.
- No Server Lag: Instant formatting with zero latency.
- Code Folding: Collapse huge arrays to focus on what matters.
- Search & Replace: Use Regex to find specific records in massive files.
Beautify & Read JSON Easily with This Formatter
Transform compact, minified JSON into readable, properly indented format with our JSON pretty print tool. Perfect for debugging API responses, reading configuration files, or making JSON data human-readable.
Fix Invalid JSON Automatically (AI Powered)
Our AI JSON Fixer can repair broken JSON automatically. It fixes single quotes, trailing commas, Python booleans, missing quotes, invalid values, and syntax errors so your JSON becomes valid and usable.
How to Format JSON Online - Step by Step
Paste or Upload JSON
Copy your unformatted JSON and paste it into the editor, or drag & drop a .json file directly onto the page.
Auto-Format or Click Format
JSON is automatically formatted on paste. You can also click the Format button for manual formatting with custom indentation.
Validate & Fix Errors
The validator highlights syntax errors with line numbers. Fix missing commas, brackets, or quotes easily.
Copy or Download
Copy formatted JSON to clipboard with one click or download as a .json file for use in your projects.
Frequently Asked Questions
Is this JSON formatter and validator free?
Yes, JSON Formatter Pro is completely free to use with no limitations. There is no signup, registration, or account creation required. All features including formatting, validation, minification, and format conversion are available immediately without any cost. The tool remains free for unlimited usage.
Is my JSON data secure?
Yes, your data remains completely private. All JSON processing happens locally in your browser using JavaScript. Your data never leaves your device and is not transmitted to any server. This local processing approach ensures sensitive information like API keys, tokens, or proprietary data stays secure on your machine.
Can it handle large JSON files?
Yes, the tool supports large JSON files efficiently. Processing happens entirely in your browser using the Monaco Editor engine, the same technology used in Visual Studio Code. Features like syntax highlighting, code folding, and validation work smoothly with files containing millions of characters without upload delays.
Can this tool fix invalid JSON?
Yes. JSON Formatter Pro includes an AI-powered JSON fixer that automatically repairs invalid JSON by fixing single quotes, trailing commas, Python values, missing quotes, and syntax errors.
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