Under 20 MB, Still Rejected: Shopify’s Other Image Limit
You made the file smaller. Shopify still says it is too large. The missing number may be pixels: an 8000 × 4000 image contains 32 million of them, even if the file is only 4 MB. Before sacrificing more image quality, check its dimensions and the limit for your exact upload field.
Sources checked September 26, 2026. This is a documentation-based troubleshooting guide with calculated examples, not a test performed in a live Shopify store.
How a 4 MB image can still be too big
Megabytes (MB) describe the stored file. Megapixels (MP) describe the number of pixels in the image. JPEG compression can reduce the first without changing the second.
For example, an 8000 × 4000 image has 32 million pixels even if its file size is only 4 MB. A message about a large image therefore needs two checks: the bytes and the dimensions.
Calculate megapixels as: width × height ÷ 1,000,000.
| Dimensions | Megapixels | Meaning |
|---|---|---|
| 8000 × 4000 | 32 MP | Above both pixel ceilings discussed below |
| 5000 × 5000 | 25 MP | Upload context matters |
| 4000 × 4000 | 16 MP | Below both pixel ceilings; still check bytes and format |
The limit changes with the upload field
Shopify’s general Uploading images guide lists 20 MP and 20 MB. It specifically explains that a below-20-MB file can trigger a size error because its pixel count is too high. That page also notes that product images have different limits.
The separate Product media types guide describes product and collection images up to 5000 × 5000 pixels or 25 MP, with files smaller than 20 MB. Use the guidance for the exact upload field you are working with; do not apply a number from another part of Shopify without checking.
A short troubleshooting sequence
- Keep the original. Work on a copy. Note the upload screen and the exact error so you can tell whether a change helped.
- Read the actual dimensions. Look in the file’s properties or image information. Do not estimate the dimensions from how large it looks on your screen.
- Calculate the pixel count. If dimensions are the problem, reducing quality alone is unlikely to solve it. Resize proportionally. An 8000 × 4000 image resized to 4000 × 2000 becomes 8 MP.
- Check file size and format separately. If the pixel count already fits but the file is too large, export a suitable format or adjust compression. Use the new file’s actual size, not the source’s size.
- Inspect the export. Look at product texture, edges, and small lettering at 100%. Keep enough detail for the intended presentation.
- Retry with the new export. Confirm that the selected filename is the edited copy. If it still fails, keep a record of the new dimensions, bytes, format, upload area, and error for further troubleshooting.
From 12.29 MB to under 1 MB—with the same pixel count
We tested our Pocket Tools image compressor with an original synthetic fabric chart. The source PNG was 12,292,930 bytes; the JPEG result was 995,771 bytes. Both files remained 3000 × 2250 pixels (6.75 MP). This demonstrates a reduction in stored size without a reduction in pixel count.
Do you need to compress every photo first?
No. Shopify’s image guidance recommends supplying the best-quality images you can and explains its storefront image optimization. Treat manual resizing or compression as a response to an actual upload constraint. Repeated exports can spend image quality without fixing the underlying problem.
A successful upload is also different from a good storefront crop. After uploading, preview the product on desktop and mobile and check how the theme frames it.
Keep a useful record
For each failed attempt, write down:
- Where you uploaded: product media, theme image, or another field
- Width × height and calculated MP
- File size and format
- The exact error message
- What you changed before retrying
This makes your next step more specific than repeatedly lowering a quality slider. No single export size guarantees acceptance by every upload field.
Prepared with AI assistance and checked against the official sources above. Signal & Steps is independent of Shopify. No affiliate links or paid recommendations are included in this article.
