Prepare images for upload

Optimize image quality and avoid errors when uploading to your Library

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Prepare images for upload

Get your image ready to upload to your Library by making sure it has the right file size, format and look; this protects the image's quality and prevents errors during the upload. You can experiment with layouts after you've added the images to your email.

You can use any image editor you're comfortable with to edit your image before uploading, but keep in mind that some image editors have an option to "Save for Web & Devices" or to "Optimize" the image for you. If you use the option, make sure you choose a resolution that shrinks the image's file size to less than 5 MB.

Size Images for Success

Shrinking the image's dimensions may also decrease its file size -- but don't make the image smaller than necessary.

  • Height - There isn't usually an ideal height because each block will adjust to fit the image's height, but if your image is being used as the email header, images <200 pixels high will fully display in email preview panes. Keep in mind that some clients (like Outlook) may clip images that have a height that spans more than 1728 pixels.
  • Header Width - Keep the header images at 600 pixels wide.  Smaller widths will stretch your image to fit the header and larger widths will stretch your email header and distort your email.
  • One-column Template Width - If you're using a one-column template, keep the image at 600 pixels wide or less. 
  • Two-column Template Width - If you're using a two-column template, keep the image at 250 pixels wide or less.
  • Three-column Template Width - If you're using a three-column template, keep the image at 150 pixels wide or less.
  • File Size - Images larger than 5 MB won't upload. Some image editors have an option to "Save for Web & Devices" or to "Optimize" the image for you. If you use the option, make sure you choose a resolution that shrinks the image's file size to less than 5 MB and don't forget to flatten any layers when you save the final image.

Not sure what dimension or file size your image has? Find out here.

Note: There are specific content standards when using Facebook Ads or the Social Campaign app tab on Facebook.


Find the Best Image File Type

Some types of images look better when saved as a specific type of file. This chart shows you which file types work best with certain types of images:

Image File Types
TypeProsConsWorks Best With
  • Small file size
  • Distorts image to reduce file size
  • Doesn't work well with text
  • Doesn't support transparency
  • Compresses when uploaded
  • Photos
  • Small file size
  • Supports basic transparency
  • Doesn't compress when uploaded
  • Limited to 256 colors
  • Images can appear grainy if they use web-unsafe colors
  • Logos
  • Simple graphics
  • Low resolution images
  • Best quality, regardless of content
  • Supports full transparency
  • Great for text
  • Can fix some distortions caused by other file types
  • Doesn't compress when uploaded
  • Larger file size
  • Won't upload If over 5 MB
  • All images

Tip: If an image won't upload as a JPG file, try saving it as a PNG or GIF file.

Image files such as a TIFF or BMP can't be stored in your Constant Contact image library, but you can use any basic image editing program to save them as a PNG, GIF, or JPG.


Improve Image Quality

Don't just upload any old image! Make it look its best:
  • Color Mode - RGB colors look best on the web. CMYK colors look best in print. Turn off any color management settings in your image editor to help prevent colors from changing when viewed online.
  • Brightness - Adjust the color level so your subject isn't hiding in the shadows or in the glare.
  • Composition - Try cropping your image to make your subject stand out. This can even be done after you've uploaded it to the Library or while you're editing your email or landing page.

Note: Images files get compressed when you upload them, which keeps the dimensions while reducing the file size and image quality. If the image is small, you may not notice the difference, but the reduction in quality can be more noticeable in larger image files. GIF and PNG files won't compress.

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