How can I optimize images for email loading speed?
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You've sent an email with gorgeous product shots, but half your subscribers are waiting 10 seconds for them to load on mobile. Image optimization fixes that.
So Start with format. JPEGs work great for photos (compress to 60-80% quality and you won't see the difference). Use PNGs for graphics or logos that need transparency. Resize images down to their display size before you upload. Don't send a 2000-pixel image that displays at 600 pixels.
Next, compress aggressively. Squoosh and TinyPNG will shrink file sizes without visual loss. Email clients load all images instantly at open (there's no lazy loading in email), so every kilobyte in your message counts on slow connections.
Use a CDN to serve images from servers closest to your recipients. This matters especially for global audiences. Check your ESP's file size limits before you hit send. Ready to test? Use Review My Emails' testing tools to flag slow-loading images in your templates.
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