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Desktop-first to mobile-first
CSS in seconds.

Paste your desktop-first CSS and get clean, optimized mobile-first output instantly. No signup. No config. Just works.

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converter.css
Input · Desktop First
                            
  .container {
    width: 1200px;
    padding: 40px;
  }

  @media (max-width: 768px) {
    .container {
      width: 100%;
      padding: 16px;
    }
  }
                        
Output · Mobile First
                            
  .container {
    width: 100%;
    padding: 16px;
  }

  @media (min-width: 769px) {
    .container {
      width: 1200px;
      padding: 40px;
    }
  }
                        

Features

Built for developer workflows

Everything you need to modernize your CSS. Nothing you don't.

Instant Conversion

Paste your CSS and get mobile-first output in milliseconds. Zero latency, client-side processing.

Mobile-First Output

Converts max-width queries to min-width. Your CSS follows modern responsive best practices.

Clean Formatting

Output is properly formatted with consistent indentation. Ready to copy-paste into production.

No Data Sent

Everything runs in your browser. Your code never leaves your machine. Zero tracking.

Handles Complex CSS

Multiple breakpoints, and edge cases — all handled correctly.

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