Optimizing image file size for emails is critical for deliverability, loading times, and user experience. Experts and marketers recommend balancing image quality with file size by using appropriate file formats (JPEG, PNG, WebP), compressing images, and resizing them to fit the display area. While some suggest an overall email size of under 100KB to avoid Gmail clipping, others aim for under 500KB or even allow up to 2MB. Using CDNs, lazy loading, and tools like TinyPNG/ImageOptim are also advised. Key considerations include responsive design, testing across email clients, and understanding the impact of file size on carbon footprint.
11 marketer opinions
Optimizing image file size for emails is crucial for avoiding spam filters, ensuring fast loading times, and improving overall deliverability. Best practices include using appropriate file formats (JPEG for photos, PNG for graphics), compressing images to reduce file size, and resizing images to fit the intended display area. Keeping the total email size (including HTML and images) under 100KB-500KB is recommended to prevent clipping and improve the user experience. Load time and carbon footprint are also factors to consider. CDNs, lazy loading, and image optimization tools can also aid in creating optimized emails.
Marketer view
Email marketer from Quora user Jane Doe explains that images should be optimized to be as small as possible without sacrificing visual quality. She notes that using tools for compression and adjusting dimensions can significantly reduce file size and improve email loading times.
2 Aug 2023 - Quora
Marketer view
Email marketer from HubSpot responds that optimizing images through compression and using appropriate dimensions is crucial for email deliverability. Reducing file size ensures faster loading and a better user experience, which can positively impact sender reputation and prevent emails from landing in the spam folder.
6 Sep 2021 - HubSpot
1 expert opinions
Laura Atkins from Word to the Wise emphasizes that image optimization is critical for email deliverability. Large images can trigger spam filters, and slow loading times can hurt engagement. Vital elements include appropriate file formats, compression, and resizing.
Expert view
Expert from Word to the Wise, Laura Atkins, explains that optimizing images is essential for email deliverability. Large images can trigger spam filters, and slow loading times can negatively impact engagement. Using appropriate file formats, compression, and resizing images are all vital elements.
30 Jul 2021 - Word to the Wise
6 technical articles
Multiple sources indicate that optimizing image file sizes is crucial for email deliverability and loading times. Gmail clips emails exceeding 102KB total size. While there's no single optimal size, aiming for under 1MB is generally recommended, but smaller is better. Choosing the right format (JPEG, PNG, or WebP) and using compression techniques are vital. Responsive images and proper resizing also contribute to performance. Consider using CSS instead of images where possible.
Technical article
Documentation from Microsoft provides some best practices that include compressing images, choosing the correct format (JPEG or PNG), and using the Picture Manager to resize your images to the desired dimensions. This helps reduce the size of your emails.
23 Oct 2021 - Microsoft Support
Technical article
Documentation from Email on Acid shares that while there's no single 'optimal' image size, aiming for under 1MB is a good starting point, but far smaller is better. They discuss how using optimized JPEG or PNG files, depending on the image type, and ensuring images are appropriately sized for their display area can improve deliverability and loading times.
16 Sep 2021 - Email on Acid
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