While you're free to choose what image dimensions, size and format you'd like your signature image to be, we have created a few best practice guidelines that we suggest you follow.

Keep image file sizes as small as possible.  Set your images to the exact width and height that you want at 72 dpi.  Even though you can "resize" the image with html parameters, email clients are not like web browsers and will sometimes drop the image parameters.  When this happens, the images will then be displayed in full size in the email history.

Image dimensions

NOTE: If you want to resize your image (alter its dimensions), we suggest you do so within your native image software (e.g. Adobe Illustrator or Photoshop) if possible to avoid any issues with different email platforms displaying these.

Ideally, your ad banners and images should be less than or equal to 700px wide and 100px high.

Dimensions: 380px x 106px

Dimensions: 500px x 100px

Image Size

10kb or less is the size recommended for each image used in your signature.

If you are using photos in your design, you may be finding it difficult to keep to this image size. Banners with fewer colours, patterns and included images are generally smaller sized.

If you're struggling with size, you can reduce the size of your image without losing quality by using this tool (or similar image compression websites and tools):
Size can cause issues by slowing down the load time of each email (this is compounded in conversation chains if your image is affixed at the end of each email).

Image Format

Crossware Mail Signature supports the upload of these file types:


Remember to always test your images on all devices and email platforms before adding these to your signatures!
Related Products: CMS M365