Email Device Previewer
Preview your email before you send it. Paste your subject line and email content to see how your message renders across desktop and mobile layouts in both light and dark modes. The built-in inspector checks your email HTML for common responsive rendering problems.
Built-In Email Rendering Inspector
The previewer checks your email content for several common issues that can cause poor rendering on mobile screens or in dark-mode clients:
Hardcoded White Backgrounds
Forcing a white background creates blinding white blocks when an email is viewed in dark mode. The inspector checks for hardcoded colors and flags them when detected.
Hardcoded Dark Text
Dark text such as #000000 can become illegible when an email client automatically inverts the canvas. The inspector flags dark font declarations that threaten contrast.
Unconstrained Images
Large fixed-width graphics trigger horizontal scrolling on smartphones. The inspector ensures all image elements contain responsive max-width: 100% properties.
How to Use the Email Previewer
- Add Your Subject Line: Enter the subject line you plan to dispatch in your campaign.
- Paste Your Email Copy: Insert plain text or compiled HTML templates into the input area.
- Render Device Previews: Click the execution button to build the four simulated viewports.
- Review the Inspector: Check flagged contrast, layout, and image warnings.
- Inspect Every Screen: Verify desktop and mobile viewports across light and dark modes.
Email Rendering vs. Deliverability
Email rendering is about how your message displays visually when opened. Email deliverability is about whether your message successfully passes MX filters to land in the primary inbox.
Responsive Email Design Checklist
Before sending an HTML campaign, verify these technical formatting benchmarks:
Email Previewer FAQ
What does the Email Device Previewer do?
It renders your email in desktop and mobile preview environments using both light and dark modes. It also analyzes the underlying HTML to flag hardcoded background colors, dark text contrast issues, and unconstrained image tags.
Can I preview HTML emails?
Yes. You can paste raw HTML email code directly into the previewer. Plain-text copy is also supported and will be rendered with natural spacing.
Does this tool test every physical email client?
No. The previewer provides standardized simulated mobile and desktop viewports. Individual mail apps (like Outlook desktop or Apple Mail) apply their own unique proprietary rendering rules.
Does a clean preview guarantee inbox placement?
No. Visual formatting and deliverability are separate technical components. Even a flawlessly formatted email requires proper SPF/DKIM DNS authentication, clean lead lists, and good sender reputation to reach the primary inbox.
Preview Before You Launch
Your email should look good before it reaches your prospects. Connect your sending mailboxes, automate warmup loops, and scale outreach with complete deliverability control.