The best image formats for email newsletters

You've just saved 40% by converting your website images to AVIF. Time to do the same for your email newsletter, right? Not so fast.

Email clients live in a parallel universe where modern image formats go to die. Here's what actually works.

The reality of email client support

| Format | Gmail | Outlook | Apple Mail | Yahoo | | ------ | ----- | ------- | ---------- | ----- | | JPEG | Yes | Yes | Yes | Yes | | PNG | Yes | Yes | Yes | Yes | | GIF | Yes | Yes | Yes | Yes | | WebP | Yes | No | Yes | Yes | | AVIF | No | No | Partial | No |

Outlook on Windows (the desktop app, used by millions of corporate users) renders emails using Microsoft Word's HTML engine. Yes, Word. That means no WebP, no AVIF, no <picture> element, and limited CSS support.

The safe choice: JPEG + PNG

For email newsletters in 2026, the reliable combination is:

• JPEG for photographs and complex images
• PNG for logos, icons, and images with transparency
• GIF for simple animations (keep them under 1 MB)

That's it. No WebP, no AVIF, no SVG (most email clients strip SVG for security reasons).

Optimising images for email

Email images need to be light because:

1. Many email clients block images by default until the user clicks "Display images"
2. Heavy emails are more likely to land in the Promotions tab or spam
3. Mobile data users will appreciate smaller downloads

Recommended settings:

• Maximum width: 600px (the standard email content width)
• JPEG quality: 72–78 (lower than web — email images are smaller on screen)
• Strip all metadata (EXIF, ICC profiles)
• Target under 200 KB per image, under 800 KB total per email

What about OG images for email links?

When someone shares your link in an email, the preview card uses Open Graph images — and these are rendered by the browser, not the email client. So your OG images can absolutely be WebP or AVIF.

The preview is fetched when the recipient clicks or when the email client pre-fetches the URL. At that point, the browser's full format support is available.

Retina images in email

Most email clients on iOS and macOS render on retina displays. To keep images sharp:

1. Create images at 2× the display size (1200px wide for a 600px email)
2. Set the width attribute to the 1× size: <img src="hero.jpg" width="600" />
3. Compress at quality 72 — the higher pixel density compensates for lower quality

The quick playbook

1. Use JPEG for photos, PNG for logos and transparency
2. Resize to 1200px wide (for 600px display width)
3. Compress JPEG at quality 72–78
4. Strip metadata
5. Keep total email weight under 800 KB

You can handle all of this in our compression tool — drop your images, set the quality, and download. For format conversion, use the converter.