Online Code Formatter & Validator
Format, validate, and minify JSON, SQL, HTML, CSS & XML instantly. 100% client-side — your code never leaves your browser.
Why Developers Love DevTools Pro
Instant Formatting
Format JSON, SQL, HTML, CSS, and XML with a single click. No delays, no loading.
100% Private
All processing in your browser. Your code never touches our servers. Zero data collection.
Multi-Language
JSON, SQL, HTML, CSS, XML — format, validate, and minify all in one tool. No sign-up.
Frequently Asked Questions
How do I format JSON online?
Paste your JSON into the input panel on the left, make sure the JSON tab is selected, and click the "Format" button. Your JSON will be instantly prettified with proper indentation. You can also click "Validate" to check for syntax errors, or "Minify" to compress it.
Is my code safe? Do you store it?
Your code is completely safe. All formatting, validation, and minification happens entirely in your browser using JavaScript. No data is ever sent to our servers. We don't log, store, or analyze any code you paste.
What code languages can I format?
DevTools Pro supports JSON, SQL, HTML, CSS, and XML. Each language has formatting (beautify), minification (compress), and where applicable, validation (syntax checking). Select the appropriate tab before processing your code.
Can I format large files?
Yes! Since processing happens in your browser, performance depends on your device. Most modern devices handle files up to several megabytes without issues. You can also use the "Upload" button to load files directly from your computer.