Substack
Last updated: Aug 29, 2025
Substack needs clean images that survive email. Use high-contrast covers that read small and keep overlays minimal—subjects lines do the heavy lifting. Keep logos simple and centered for headers and social shares.
Best Practices
- Use large, uncluttered cover images that read on mobile.
- Keep on-image text minimal; let the subject line do the work.
- Export sharp JPEG/PNG with gentle compression.
- Center logos; avoid edge-hugging details in headers.
- Test in light/dark backgrounds for contrast.
Pro Tips
- Prefer photos/graphics with clear focal points.
- Leave generous padding if adding text overlays.
- Use consistent color/typography across issues.
- Check how the image renders in email previews.
- Upload at native aspect to reduce re-compression.
Visual Previews
Post Cover (Recommended)
3:2 · Image
1500 x 1000 px
Preview shows relative aspect only. Export at the listed resolution for best quality.
Post Cover (Wide Alt)
16:9 · Image
1600 x 900 px
Preview shows relative aspect only. Export at the listed resolution for best quality.
Publication Logo
1:1 · Image
512 x 512 px
Preview shows relative aspect only. Export at the listed resolution for best quality.
Header Banner
2:1 · Image
2560 x 1280 px
Preview shows relative aspect only. Export at the listed resolution for best quality.
Sizes
Post Cover (Recommended)
- Dimensions:
- 1500 x 1000 px
- Aspect Ratio:
- 3:2
- Format:
- Image
Post Cover (Wide Alt)
- Dimensions:
- 1600 x 900 px
- Aspect Ratio:
- 16:9
- Format:
- Image
Publication Logo
- Dimensions:
- 512 x 512 px
- Aspect Ratio:
- 1:1
- Format:
- Image
Header Banner
- Dimensions:
- 2560 x 1280 px
- Aspect Ratio:
- 2:1
- Format:
- Image
| Type | Dimensions | Aspect Ratio | Format |
|---|---|---|---|
| Post Cover (Recommended) | 1500 x 1000 px | 3:2 | Image |
| Post Cover (Wide Alt) | 1600 x 900 px | 16:9 | Image |
| Publication Logo | 512 x 512 px | 1:1 | Image |
| Header Banner | 2560 x 1280 px | 2:1 | Image |
FAQ
What image should I use as a post cover?
Use a clean 3:2 or 16:9 image at ~1500px+ width for sharp display and email previews.
How big should my publication logo be?
Square logos at 512×512+ work well across the app and web.
Any safe zones?
Substack is minimal—center content and keep edges clean for good results.
Substack Media Dimensions | SocialSpec
