Most email is mobile
A majority of email is opened on phones, yet many signatures are designed only for desktop. A signature that overflows or shrinks on mobile undermines an otherwise professional email.
Design narrow-first
Keep total width under ~600px, prefer stacked or compact layouts, and avoid wide multi-column structures that force horizontal scrolling on small screens.
Create a professional email signature in minutes
Use KeyStamp's AI Signature Studio to generate, customize, preview, and export email-safe signatures for your team.
Readable sizes and tap targets
Don't shrink text below ~11px, and make sure linked phone numbers and CTAs are large enough to tap comfortably.
Test on real widths
Preview at phone width and confirm images scale, the divider holds, and nothing wraps awkwardly.
How KeyStamp helps
KeyStamp is an AI-powered email signature creator. Describe what you need and it generates a professional, email-safe signature you can refine visually — then manage branding, templates, and employee details from one place and export clean HTML that renders everywhere.
Frequently asked questions
What width should a mobile signature be?
Should I make a separate mobile signature?
Why do my links look tiny on mobile?
Ready to build better email signatures?
Start with KeyStamp and create professional, brand-consistent email signatures using AI-powered templates.