Summary
Low email open rates when using images are multi-faceted. While images themselves may not directly cause deliverability issues, factors such as large image sizes slowing load times, image-heavy emails with low text-to-image ratios triggering spam filters, and email client image blocking can negatively impact open rates. Template length can cause clipping, affecting tracking pixels. Inconsistent rendering of background images and unreliable image hosting contribute to poor user experience. Optimize images for web, use alt text, choose appropriate formats, ensure reliable hosting, personalize/brand images, and ensure images are relevant, and monitor deliverability. Check open rates across providers to identify filtering issues and ensure proper tracking pixel implementation.
Key findings
- Filtering: Image-heavy emails with low text-to-image ratios can trigger spam filters.
- Image Size & Loading: Large image sizes slow loading times, affecting user experience, especially on mobile.
- Image Blocking: Many email clients block images by default, requiring alt text for message conveyance.
- Template Length: Long email templates can be clipped, preventing tracking pixel loading.
- Inconsistent Rendering: Background images have inconsistent rendering across clients.
- Hosting Reliability: Unreliable image hosting results in broken images and poor user experience.
- Engagement: Images that do not add value and are purely decorative, can hurt engagement.
Key considerations
- Text-to-Image Balance: Maintain a balanced text-to-image ratio to avoid spam filters.
- Image Optimization: Optimize images for web (size, format) to improve loading times and mobile experience.
- Alt Text Usage: Use descriptive alt text for accessibility and when images are blocked.
- Client Compatibility: Design for consistent rendering across different email clients (avoid relying on background images).
- Reliable Hosting: Choose reliable image hosting for consistent image availability.
- Personalization: Incorporate personalization and branding to boost engagement and recognition.
- Relevance: Images should be relevant and not purely decorative
- Monitor Deliverability: Monitor deliverability metrics, including open rates across providers and tracking pixel implementation.
What email marketers say
12 marketer opinions
Low email open rates when using images can stem from various factors. Deliverability issues may arise due to image-heavy emails triggering spam filters, especially with a low text-to-image ratio. Large image sizes can slow loading times, impacting user experience, particularly on mobile. Many email clients block images by default, necessitating the use of alt text to convey the message. Monitoring open rates across different providers can help identify filtering issues. Ensuring the open tracking pixel loads correctly (HTTPS) is crucial. Personalizing images and branding them can increase engagement. Finally, ensure that the images are optimized and not decorative.
Key opinions
- Filtering: Image-heavy emails, especially with low text-to-image ratios, can trigger spam filters.
- Image Size: Large image sizes slow loading times, negatively impacting user experience and open rates.
- Image Blocking: Many email clients block images by default, reducing the effectiveness of image-heavy emails.
- Mobile Optimization: Unoptimized images can cause issues on mobile devices, affecting engagement.
- Personalization: Personalized and branded images can increase engagement and open rates.
- Tracking: Ensure that your email tracking pixel is implemented and active, using HTTPS.
Key considerations
- Text-to-Image Ratio: Maintain a balanced text-to-image ratio to avoid triggering spam filters.
- Image Optimization: Optimize images for web use to reduce file size and improve loading times, especially on mobile.
- Alt Text: Use descriptive alt text for images to ensure the message is conveyed even when images are blocked.
- Provider Monitoring: Monitor open rates across different email providers to identify potential filtering issues.
- Engagement: Image should serve a purpose and be relevant in the email, not just decorative.
- Branding: Ensure imagery is consistent with branding to build familiarity with recipients
Marketer view
Email marketer from Email on Acid shares that many email clients block images by default, impacting the effectiveness of image-heavy emails. Using alt text and optimizing the text-to-image ratio can mitigate this issue, ensuring that the message is still conveyed even when images are blocked. This maintains user interest and helps improve open rates.
10 Dec 2023 - Email on Acid
Marketer view
Email marketer from Mailjet Blog explains that large image sizes can slow down email loading times, leading to a poor user experience and potentially impacting open rates, especially on mobile devices. Optimizing images for web use can improve loading speed and engagement.
6 Aug 2022 - Mailjet Blog
What the experts say
3 expert opinions
Low email open rates in relation to image use can stem from template length leading to clipping (affecting pixel tracking), the use of purely decorative and irrelevant images harming engagement, and broken images in HTML emails damaging sender reputation.
Key opinions
- Template Length: Long email templates can be clipped by Gmail, preventing the open-tracking pixel from loading and reducing recorded open rates.
- Image Relevance: Using purely decorative images that don't add value can decrease user engagement.
- Broken Images: Broken images in HTML emails can negatively impact sender reputation if they occur frequently.
Key considerations
- Template Optimization: Ensure email templates are not too long to avoid clipping by email clients.
- Image Value: Use images that are relevant and add value to the email content, rather than just decorative elements.
- Image Integrity: Verify that all images in HTML emails are loading correctly to avoid damaging sender reputation.
Expert view
Expert from Email Geeks advises checking if the new email template is too long, as Gmail clipping the email (and the open-tracking pixel at the bottom) can reduce open rates.
8 Jan 2023 - Email Geeks
Expert view
Expert from Word to the Wise, Laura Atkins, explains that using purely decorative images, or images that don't add value can hurt engagement. Ensure images are relevant and serve a purpose within the email content.
20 Jul 2021 - Word to the Wise
What the documentation says
4 technical articles
Low email open rates related to images can stem from inconsistent rendering of background images across email clients, unoptimized image sizes affecting loading times, unreliable image hosting leading to broken images, and the use of inappropriate image formats. Ensuring consistent rendering, optimized image sizes, reliable hosting, and proper image formats are crucial for improving user experience and open rates.
Key findings
- Rendering Inconsistency: Inconsistent support for background images across email clients can lead to rendering issues and a poor user experience.
- Image Optimization: Unoptimized image sizes lead to slower loading times, negatively impacting user experience, especially on mobile.
- Hosting Reliability: Unreliable image hosting results in broken images, causing a poor user experience.
- Image Format: Using inappropriate image formats can increase file size and affect image quality.
Key considerations
- Alternative Design: Use alternative design techniques to ensure consistent rendering across different email clients instead of relying heavily on background images.
- Compression: Compress images to reduce file size without significantly compromising quality to improve loading times.
- Reliable Hosting: Host images on reliable servers to ensure they are always available and load quickly.
- Format Selection: Select appropriate image formats (JPEG for photos, PNG/GIF for logos and icons) and optimize for file size.
Technical article
Documentation from Sendgrid explains the importance of hosting images on reliable servers. If image servers are down or slow, images won't load, leading to a poor user experience. This can negatively impact open rates. Hosting images on robust servers ensures images are always available.
8 Jul 2021 - Sendgrid
Technical article
Documentation from W3Schools advises selecting the appropriate image format for email. JPEG is good for photos. PNG or GIFs are usually best for logos, icons, and images with text. Also ensure you optimize for file size.
26 May 2022 - W3Schools
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