Email images should be 600 pixels wide for maximum compatibility across email clients. Most email templates use a 600px content width, and images wider than this will be resized by the email client, potentially causing display issues.
For email headers and banners, 600x200 to 600x300 works well. For inline content images, 600x400 or 600x340 provides a good balance. For email signature images, keep them under 200px wide.
With ImgTools, upload your image and resize with the width set to 600. Adjust the height based on your email layout needs. Save as JPEG at 75-80% quality for fast loading in email.
Keep individual email images under 100KB and total email weight under 1MB for the best deliverability and display.
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