How We Test
Email Clients
Eliminating the guesswork from email signature design through rigorous, redundant device testing.
Classic Outlook Desktop
Word Engine
Supported Versions: 2016, 2019, 2021, LTSC
New Outlook for Windows
Web View
Supported Versions: Current Preview & Stable
Gmail Web / Workspace
Web-Safe
Supported Versions: Chrome, Safari, Edge, Firefox
Apple Mail macOS
WebKit
Supported Versions: Ventura, Sonoma, Sequoia
iOS / iPadOS Mail
Mobile WebKit
Supported Versions: Latest 3 iterations
Gmail for Android
Native Wrapper
Supported Versions: Material Design 3 Latest
Our 12-Point
Testing Checklist.
Before a template is released on InboxSign, it must pass a 100% "Perfect Visual" check on every device in our stable. We don't just "look" at it—we measure it.
- 96 DPI Consistency
- Inline CSS stripping
- Image ALT text rendering
- Social Link pathing
- Dark Mode adaptation
- Mobile Screen stacking
Layer Inspection
We manually inspect the HTML nesting depth to prevent Microsoft Word's engine from over-indenting content.
Preference Scaling
Testing against "Zoom" settings (125%, 150%) in Windows to prevent layout overflow bugs.
Reply/Forward Stability
Signatures are tested after 5 back-and-forth replies to ensure the HTML doesn't "leak" or break.
Need Support for or Specific Device?
Is your signature looking strange on a specific legacy client? Our team performs daily updates to our HTML engine to ensure stability. Contact our support docs if you find a rendering issue.
Contact Tech Team →