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- We recommend at least 300px so that when the image is full width on mobile, it will not be blurry/grainy.
- Check the file size of your image before uploading. Keep images under 300KB, and ideally under 200KB in file size. Why? Large Large images make it more likely for your emails to get removed by spam filters, cost more data to load (especially an issue for mobile users), and slows down the speed at which an email loads. Users are less likely to engage with or read an email if the photos take more than a second to load.
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How to decrease image file size
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