Why does my email signature shrink when sent from an iPhone?
When your email signature includes wide elements - such as a fixed-width table, a wide banner, or long un-wrapped text - your iPhone automatically scales down the entire email to fit its smaller screen size. These scaled-down dimensions are saved in the sent message, causing the signature to appear tiny when opened in Apple Mail on a MacBook or desktop Mac.
Cause: Mobile devices automatically shrink email content that exceeds the width of the phone screen ("Fit Screen" behavior), and that reduced scale carries over when the message is viewed on a Mac.
Device limitation: Automatic screen-fitting is a built-in iOS device behavior that cannot be turned off through signature code alone. However, you can prevent your signature from triggering automatic scaling by following the installation and sizing guidelines below.
How do I prevent my signature from shrinking on iPhone and Mac?
To stop your iPhone from scaling down your MySignature email signature before sending, follow these steps:
Reinstall your signature properly on iOS: Follow every step in the guide on how to install the signature on iPhone/iPad to ensure iOS preserves your signature formatting.
Limit your signature width to 450px: Keep your overall MySignature layout width at or below 450px, adjusting based on your longest line of contact information so it does not exceed the mobile screen width.
Enable text wrapping for disclaimers: Configure any legal disclaimers or long text blocks to wrap onto multiple lines rather than stretching horizontally across the signature.
Resize and upload high-resolution images: Resize your signature images in an image editor to match the exact width and height required by your MySignature template, using a PNG file at 300 DPI resolution. Upload the image at 3 times its display size (for example, upload a 450x450 pixel image if your logo displays at 150x150 pixels in the template).
Need more help?
If you have other questions about formatting your signature on iPhone or Mac, check our Knowledge Base for more articles, or contact our Support Team via live chat or email.