Do images in email and PDF attachments affect email deliverability?

Email marketer from Email on Acid explains that missing or irrelevant alt text for images can harm deliverability and accessibility. Providing descriptive alt text ensures that users with image loading disabled or using screen readers can understand the content, improving engagement and sender reputation.

Email marketer from Stack Overflow shares that embedding executable code or macros within PDF attachments significantly increases the risk of being flagged as spam, leading to deliverability problems. Avoid including such elements in PDFs attached to emails.

Email marketer from Reddit shares that hotlinking images (linking directly to images hosted on another server) can negatively impact deliverability if the linked server is unreliable or if the image is removed, leading to broken images and a poor user experience.

Email marketer from Mailjet Blog shares that while PDFs are generally acceptable, including unusually large PDF attachments or password-protected PDFs can raise red flags with spam filters, negatively impacting deliverability.

Email marketer from Litmus Blog discusses how unoptimized images for mobile devices can lead to slow loading times and poor user experiences, potentially affecting engagement metrics and deliverability. Using responsive image techniques is recommended.

Email marketer from Neil Patel's Blog shares that large image sizes can negatively impact deliverability. Optimizing images for the web before including them in emails is important to reduce file size and improve loading times, which can affect spam scores and user experience.

Email marketer from Sendinblue Blog explains that using too many images or a single large image without sufficient text can trigger spam filters. A good text-to-image ratio is crucial for maintaining good deliverability.

Email marketer from HubSpot Blog shares that inconsistent use of images and branding elements in emails can lead to confusion and distrust among recipients, potentially increasing spam complaints and negatively affecting deliverability. Maintain a consistent brand identity in all email communications.

Email marketer from Email Geeks shares that emails with multiple links and no images are more susceptible to being marked as spam, especially when sent multipart, which could impact deliverability.

Expert from Email Geeks explains there is no need for an image in email for better deliverability.

Expert from Email Geeks responds to concerns about PDFs, clarifying that while they can sometimes be a deliverability issue (especially longer PDFs that might hide malware), the mere presence of a PDF isn't inherently problematic.

Expert from Word to the Wise explains that embedding images as attachments instead of using linked images can sometimes be preferable as it prevents tracking pixels from being loaded, which could be a privacy benefit. However, larger message sizes may impact deliverability.

Expert from Spam Resource highlights that certain types of content, including potentially malicious attachments or those with misleading or deceptive subject lines, can cause emails to be flagged as spam. Ensure attachments, including PDFs, are safe and relevant to the recipient.

Expert from Email Geeks cautions that having ".com" in the PDF name can cause deliverability issues.

Documentation from Google Postmaster Tools indicates that high spam rates reported by users for emails containing large images or attachments can negatively affect your sender reputation and lead to deliverability issues.

Documentation from RFC 5321 defines technical specifications for email and states that excessively large attachments can lead to delivery failures due to server limitations and potential triggering of spam filters.

Documentation from Spamhaus explains that spammers often embed text within images to bypass text-based spam filters. A high volume of emails containing primarily images without sufficient text can lead to being flagged as a source of image spam, harming deliverability.

Documentation from Microsoft explains that exceeding the email message size limits imposed by Exchange Online can result in non-delivery. Large images and PDF attachments contribute significantly to the overall message size, so keeping them within limits is essential for ensuring deliverability.