Email Signature Width
The horizontal pixel width of an email signature, conventionally 600 pixels for desktop rendering and 320 pixels for narrow mobile fallback.
What is Email Signature Width?
Email signature width refers to the horizontal pixel dimension of the signature block. The de facto convention is 600 pixels wide for desktop rendering, because Outlook desktop's preview pane historically rendered messages at 600 pixels and broader email design followed. Wider signatures cause horizontal scrolling in narrow preview panes and look unprofessional. Mobile clients render at narrower viewports (320 to 400 pixels), so responsive signatures collapse to single-column layouts below a media query threshold. Width is also constrained by the image assets inside the signature: a logo that is 800 pixels wide forces horizontal scrolling, while a logo that is 400 pixels wide is comfortably within the 600-pixel signature container. Designers typically build signatures at 600 pixels with a single content column option and a two-column option (logo plus contact details side-by-side) where the two-column layout collapses on mobile.
Also known as
How does SyncSignature implement Email Signature Width?
SyncSignature templates are built at the 600-pixel desktop convention with mobile fallback layouts at 320 pixels. Template designs are validated at multiple viewport widths during the design review.