Email newsletter images are different from web images — email clients have strict rules, many block images by default, and rendering varies wildly between Gmail, Outlook, Apple Mail, and mobile clients. Here is how to create email-ready images that look great everywhere.
Email Newsletter Image Requirements
| Specification | Recommended |
|---|---|
| Width | 600 px (standard email width) |
| Hero image height | 200–400 px |
| File size per image | Under 200 KB |
| Format | JPG (best) or PNG |
| Colour mode | sRGB (not CMYK) |
Why Email Images Need Special Treatment
- Many email clients block images by default — images must have descriptive alt text
- Outlook uses Word's rendering engine — complex image styling often breaks
- Email inbox width is typically 600px — wider images are resized and can look blurry
- Retina displays require 2× resolution images (1200px wide) that display at 600px
Creating Email Images Free
Upload your image to imgresizr.com. Resize to 1200px wide (which will display at 600px on most email clients — 2× for Retina). Keep file size under 200KB by compressing to 80–85% quality. Avoid transparency in email images — use white or solid backgrounds instead (PNG with transparency renders poorly in Outlook). Download as JPG and embed in your email template.
Email Image Best Practices
- Always add alt text — many recipients see alt text before images load
- Do not put important information only in images — use supporting text too
- Test your email in multiple clients before sending
- Use a max-width: 100% CSS declaration so images resize on mobile
Create email newsletter images at the right size and format at imgresizr.com — free and email-client compatible.