Alternative Text (Alt-Text) is the fallback mechanism that displays when an image does not render within an Email Client or ESP. The source of the name comes from the tag assigned within the HTML code (alt=).
Alt text Best practices:
- Keep alt text to less than 125 characters including spaces.
- Use basic punctuation like periods and commas.
- Quotation marks will break alt text.
- Describe image accurately and concisely.
And here’s an example of how it would look with and without alt text.
So why do we recommend include it within an email template?
- For Image Heavy Designs - When templates lack a lot of text-based content, adding alt-text to the added images will give the recipient clues to what the message is when images are not enabled.
- Content Best Practice - ISPs will use different data points to apply content-based filtering rules within a mailbox. Since including ‘Alt-Text’ is a best practice, including this information in the email body, will help give ISPs more information to make a content-based decision for the email design.
- Alt Text is Supported at All ISPs and Email Clients - Not all email clients and ISPs will display images by default (Half of the email space will not display images when an email is opened). Alt Text is supported globally and will ensure that a template can read in places when images don’t work.