Recommended Substack Dimensions
When your Substack newsletter is shared on social media, the preview image is what readers see first. Getting the dimensions right ensures your content looks polished across Twitter, Facebook, LinkedIn, and other platforms.
| Asset | Dimensions | Aspect Ratio | Max Size | Format |
|---|---|---|---|---|
| Social preview | 1456 × 1048 px | ~1.4:1 | 10 MB | PNG / JPG / GIF |
Why it matters: Substack uses these images when your newsletter is shared on social media — a compelling preview drives click-throughs and grows your subscriber base.
File Format Tips
Choosing the right file format can make a noticeable difference in how your preview image renders across platforms:
- PNG — Best for text-heavy previews, logos, and graphics with sharp edges. Lossless compression preserves crisp type.
- JPG — Ideal for photographic backgrounds and complex imagery. Smaller file sizes at the cost of slight compression artifacts.
- Max 10 MB — Keep files under the limit to avoid upload failures. Aim for the smallest file size that maintains quality.
- Export high quality — Always export at the full 1456 × 1048 resolution. Upscaling a smaller image will appear blurry on retina screens.
Common Mistakes
- Wrong aspect ratio — Using dimensions other than ~1.4:1 causes awkward cropping or letterboxing when shared.
- Low resolution — Images below 1456 × 1048 appear pixelated, especially on high-DPI mobile screens.
- Text too small — Social thumbnails render at reduced sizes. If your headline text is tiny at full size, it will be unreadable in a feed.
- Ignoring card previews — Twitter and Facebook crop differently. Preview your image in both card formats before publishing.
- File too large — Exceeding the 10 MB limit causes upload failures. Compress JPGs or optimize PNGs to stay within bounds.
How Typography Studio Pro Helps
Smart Banner Hub’s Typography Studio Pro makes creating perfect Substack social preview images simple and effortless:
- Perfect Dimensions: Automatically sized to 1456 × 1048 pixels — select Substack from the dropdown and the canvas resizes instantly.
- Unified Platform: One tool for every social platform. Switch between Substack, LinkedIn, YouTube, and more without leaving the editor.
- Professional Controls: Drag, resize, and rotate text with precision using our breakthrough interactive canvas.
- Two Design Approaches:
- Clean Text: Professional typography with perfect readability.
- AI-Powered DBSCAN: Unique mathematical clustering visuals — world-first technology exclusive to Smart Banner Hub.
- Advanced Color Systems: Color by individual words, complete lines, or mathematical precision.
- Custom Backgrounds: Upload your own images or choose from mathematical patterns and solid colors.
- Real-Time Preview: See your design update instantly as you make changes.
- Free Preview: Try before you buy — no account required to start designing.
Banners for Other Platforms
Typography Studio Pro offers unified banner creation for all major platforms:
- LinkedIn Banners — Professional headers for your career profile
- YouTube Banners — Eye-catching channel art for content creators
- Medium Banners — Distinctive headers for your publication
- Facebook Banners — Professional cover photos for your page
- GitHub Banners — Showcase your repositories professionally