Email Mobile Responsiveness Checker

Email Mobile Responsiveness Checker lets you preview how your HTML email renders across 6 device sizes — from iPhone SE to desktop — side by side. See exactly where your layout breaks, where text becomes unreadable, and where buttons become too small to tap.

The tool also scans your HTML for common responsive design mistakes: fixed widths, missing viewport tags, absent media queries, tiny fonts, oversized tables, and non-responsive images. Everything runs in your browser.

• 6 device previews: iPhone SE, iPhone 14, Android, iPad Mini, iPad, Desktop
• Pixel-accurate widths: Each iframe renders at the exact device viewport width
• Responsive issue scanner: Detects 10+ common mobile email problems
• Side-by-side or single view: Compare devices or focus on one
• Landscape toggle: Switch between portrait and landscape orientations
• Zoom to fit: Scale previews to fit your screen while maintaining proportions
• Starter template: Responsive email template with media queries

1. Paste your HTML email code
2. Click Check to see all device previews
3. Review the issues panel for responsive problems
4. Switch between device sizes to find breakpoints

• Catch mobile layout breaks before sending
• See exactly which devices your email works on
• Actionable issue detection with fix suggestions
• Free, private, runs in your browser