Shopify resizes your images on the fly — but it can only resize down. Upload too small and product zoom looks pixelated; upload way too big and page loads slow down. Below is the reference every Shopify shop should keep handy.
The numbers Shopify cares about
| Image type | Recommended size | Max allowed |
|---|---|---|
| Product photos | 2048×2048 px (square) | 4472×4472 px, 20 MB |
| Thumbnails | Generated automatically | — |
| Collection images | 1024×1024 px | — |
| Slideshow / hero banner | 1920×1080 px (16:9) | — |
| Favicon | 32×32 px | — |
The aspect ratio question
Shopify supports any aspect ratio, but most themes look best with consistent ratios across a collection. Pick one and stick with it:
- Square (1:1) — most flexible, looks clean in grids and on mobile. The default recommendation.
- Portrait (4:5) — great for apparel and tall products, especially for Instagram cross-posting.
- Landscape (3:2 or 16:9) — best for furniture, wall art, and lifestyle shots.
File format
Upload JPG for product photos (smaller files, fine quality). Upload PNG only when you need transparency. Shopify automatically converts to WebP when the customer's browser supports it, so you don't need to handle that yourself.
SEO file naming
Shopify uses your filename as the basis for the image URL and the default alt text. Two quick wins:
- Name files descriptively:
blue-linen-tote-bag-front.jpgbeatsIMG_4729.jpg. - Use hyphens, not underscores or spaces. Google reads hyphens as word separators.
- Write proper alt text in the Shopify admin — short, descriptive, no keyword stuffing.
If your source photos are too small
Lots of sellers have an inventory of older product photos shot at 1000–1500 pixels. Re-uploading at 2048+ is the difference between sharp zoom and soft zoom. Two ways to fix it:
- Re-shoot at higher resolution (best when you can).
- Run them through twil, which outputs 4K (3840×3840) for Pro accounts. The model also relights and cleans the background while it upscales — a one-pass refresh for an old catalog.
What page speed cares about
Shopify automatically serves the smallest-needed size from your master upload, so a larger source file rarely hurts page speed directly. What does hurt: having dozens of uncompressed PNGs where JPGs would have done. Keep PNG for transparency and logos. Use JPG for everything else.
Next read: 7 Product Photo Mistakes That Quietly Kill Your Sales · Studio-Quality Product Photos Without a Studio