Mailgun Inline Images: Best 9 Tricks to Embed Images in Emails Easily




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Mailgun Inline Images: Best 9 Tricks to Embed Images in Emails Easily
Why Use Mailgun Inline Images?
Images in emails improve engagement—plain and simple. The Mailgun inline images feature allows you to embed visuals directly into your email content, avoiding issues with blocked external images. Using inline images with tools like Aotsend enables branding and personalization at scale.
Trick 1: Use CID References in HTML
In your HTML body, refer to inline images with <img src="cid:myimage">
. The “cid” identifier matches the image name specified during sending.
Trick 2: Use the 'inline' Parameter
When calling the Mailgun API, add your image like this:-F inline=@/path/to/logo.png
. This makes the image accessible for inline embedding.
Trick 3: Unique Image IDs
Always give each Mailgun inline images attachment a unique Content-ID, especially when sending multiple images in one email.
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Trick 4: Use Base64 in Development
When previewing locally or in testing environments, you may encode images in Base64, although this isn’t ideal for production. Mailgun inline images are far better handled via CID.
Trick 5: Automate Image Insertion with Aotsend
Let Aotsend automate the embedding of mailgun inline images via templates. It pulls assets dynamically and embeds them without you writing any API call manually.
Trick 6: Inline Image Fallbacks
Some email clients might block images. Add alt text and design for graceful degradation. This ensures the email is readable even if the image doesn't load.
Trick 7: Optimize Image Sizes
Always compress your inline images. Large attachments increase email size and can trigger spam filters.
Trick 8: Test Across Clients
Different clients render mailgun inline images differently. Test in Outlook, Gmail, Apple Mail, and others to ensure consistent appearance.
Trick 9: Keep Inline Images Legal
Ensure any images used comply with copyright law. Especially for marketing emails via platforms like Aotsend, proper licensing is crucial.
Conclusion
Mastering mailgun inline images can dramatically improve your email marketing. These 9 tricks help you embed images effectively and ensure your emails are engaging, compliant, and professional. Combine Mailgun’s power with Aotsend’s automation to deploy branded, image-rich emails without writing complex code.