What is the optimal image file size for emails to avoid spam filters and ensure fast loading times?
Summary
What email marketers say11Marketer opinions
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.
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.
Email marketer from Reddit user u/EmailPro2020 responds that keeping the total email size, including images, below 500KB is a reasonable target. He adds that testing emails with different image sizes and email clients is essential to ensure optimal display and deliverability.
Marketer from Email Geeks shares that file size often affects Gmail clipping based on code, not images. Overall weight was more of a factor when internet connections weren’t as fast. Image optimization is always a good practice. Responsive versions with smaller options can load faster on mobile, and testing is recommended.
Email marketer from StackOverflow user User456 says that while there's no hard limit, best practice is to keep the total email size under 2MB, including all images and HTML, to prevent deliverability issues. They advise balancing image quality with file size and using image optimization tools.
Email marketer from Mailjet explains that optimizing images for email involves using the correct file format (JPEG for photos, PNG for graphics), compressing images to reduce file size without sacrificing quality, and resizing images to fit the intended display area. This helps to minimize loading times and avoid potential spam triggers.
Email marketer from EmailToolTester responds that using tools such as TinyPNG or ImageOptim is key in compressing images without losing quality which helps to improve email loading times. They recommend resizing images before uploading them to your email marketing platform.
Email marketer from Campaign Monitor shares that keeping total email size under 100KB, including images, helps ensure fast loading and reduces the risk of emails being clipped by email clients like Gmail. They advise optimizing images and using appropriate compression techniques.
Marketer from Email Geeks explains file size is a best practice for load time and it is generally fine to exceed 1MB within reason, especially if it is US only. If it is worldwide, consider removing some frames.
Marketer from Email Geeks mentions load time and your carbon footprint are also impacted by file size.
Email marketer from EmailGeekForum user EmailGuru explains that using a Content Delivery Network (CDN) to host images can help to reduce the load on your server and improve email loading times for recipients. They also advise to use lazy loading for images to improve the initial loading speed.
What the experts say1Expert opinion
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.
What the documentation says6Technical articles
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.
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.
Documentation from W3C explains that reducing image size can significantly improve website and email loading times. It is important to select the correct image format, use appropriate compression techniques, and resize images to the optimal dimensions.
Documentation from Litmus explains Gmail clips emails larger than 102KB, so keeping your total email size below this limit—including HTML, text, and images—is crucial. They recommend optimizing images aggressively and using CSS instead of images where possible.
Documentation from Google Developers states that optimizing images for web and email involves choosing the right format (JPEG, PNG, or WebP), compressing images to reduce file size, and using responsive images to adapt to different screen sizes. This improves performance and user experience.
Documentation from Mozilla explains that choosing the correct image format (JPEG for photographs, PNG for graphics with transparency) is vital to ensuring a low file size while retaining sufficient image quality. They elaborate on how different image formats handle compression and color depth.