Images in emails – the good, the bad and the ugly

4 minute read

We get a lot of questions about using images in emails, so we’ve compiled a list of tips and tricks to help you get more from your imagery.

Dimensions
Making sure your image is the right size for your email before you add it to your campaign is essential. If you resize your image after uploading it, it will be distorted and grainy.

Resize your images to the correct width and height and make sure the resolution is set to 72dpi before you upload them. To do this you’ll need an image editing tool – there’s a good list of free photo editors available here: http://graphicssoft.about.com/cs/imageediting/tp/freephotoedw.htm

File Size
It’s important to compress your images as much as you can to make sure that they load as quickly as possible for your users. Resizing the image to the correct dimensions will help a lot, as will choosing the correct file type to save it as. In general, photographs should be saved as JPEGs and any image using flat blocks of colour should be saved as a GIF.

We recommend that you keep each image well below 40Kb in size – and the Sign-Up.to system won’t allow you to upload images larger than 100Kb into your campaigns. If you are saving images as JPEGs try experimenting with the ‘quality’ setting to see how small you can get the file without negatively affecting the image quality.

It’s not just the size of individual images that’s important though. You also need to keep the total file size of your email as low as possible – which leads neatly on to our next point….

Design
It’s absolutely vital that your campaign is readable without images being loaded. The key points of your campaign should always be present as text and not images. Not only will this keep the size of your campaign down but it will allow users who don’t load images to read your campaign.

Almost all of the newer email clients don’t load images until a user requests it, so if your campaign can’t be understood without images you are likely to see a much lower response rate, and this can also cause your campaign to be picked up as spam.

ALT Text
When you add an image to your campaign you have the option to add Alt (alternative) text, which is displayed if the image is not loaded. It’s always a good idea to set this as it will aid users without images loaded and also any visually impaired subscribers who use screen readers to access your email. This isn’t a substitute for having the key points of your campaign in the body text of your email though as it’s not as legible and some email clients will not display the alt text properly.