The quick check
Most upload errors come from one of four things. Check these first:
- The pixel size matches one of the accepted sizes for the slot you are uploading to, exactly. For the main iPhone slot that is 1179 × 2556, 1206 × 2622 portrait.
- The file is a real PNG or JPEG, not another format with a renamed extension.
- There is no alpha channel or transparency. Apple's page says: “Images can't include alpha channels or transparencies.”
- You have 1 to 10 screenshots in each device size you fill.
The free screenshot validator checks the size, alpha channel and format for a whole folder at once, says which file fails and why, and can fix it for you. Nothing is stored.
“The dimensions of one or more screenshots are wrong”
The dimensions of one or more screenshots are wrong.
At least one file in the set isn't one of the exact sizes that slot accepts. App Store Connect doesn't round or crop for you, so a file that is a few pixels off is refused. Common causes:
- The wrong slot. Each display size has its own list. A screenshot that is right for iPad 13" is wrong in the iPhone slot, and the other way round. See every slot's sizes in the App Store screenshot sizes guide.
- A resized or cropped export. Design tools often export at 1x or 2x of a frame that isn't the store size, or trim a pixel off one edge.
- Portrait and landscape mixed up. Both are accepted, but width and height must match one of the listed pairs.
- A real device screenshot that isn't a store size. Some phones capture at a resolution Apple doesn't list for any slot. Simulator screenshots of the device Apple names for a slot are a safer start.
Fix: find the file with the odd size (the validator lists each file's size) and export it again at an accepted size for that slot. If the shape is close, the validator's fixer can resize it to the nearest accepted size.
“One or more screenshots are in the wrong format”
One or more screenshots are in the wrong format
Apple accepts .jpeg, .jpg and .png files. This message is reported on Apple's developer forums even for files with the right size and extension, and Apple hasn't posted an explanation there. What developers report worked for them:
- Exporting the file again from the design tool instead of uploading the original.
- Converting it to the other accepted format: PNG to JPEG, or JPEG to PNG.
- Checking the file really is what its name says. A HEIC or WebP file renamed to .png is still a HEIC or WebP file.
These are reports from other developers, not an official fix. If none of them work, contact Apple Developer Support with the file.
“One or more screenshots aren't in the RGB color space”
One or more screenshots aren't in the RGB color space
In one forum thread with this error, the file had a Display P3 colour profile, and a developer reported that exporting it again with “Export for Web” (which usually saves in sRGB) and then clearing the browser's website data made the error go away. Other posts had no confirmed fix. Things to try:
- Export the screenshot again as sRGB. Files from a Mac screenshot or a design tool set to Display P3 are worth converting first.
- Make sure the file isn't CMYK or greyscale.
- Clear the site data for App Store Connect in your browser, sign in again and retry.
Phonepose downloads are always saved as sRGB with no alpha channel, so they don't hit this one.
“You must upload a screenshot for 13-inch iPad displays”
Unable to add for review: You must upload a screenshot for 13-inch iPad displays.
This appears when you add a version for review and a required slot is empty. Every iPhone app needs screenshots in iPhone with Dynamic Island, medium (6.1" / 6.3"), and an app that runs on iPad also needs iPad 13". Developers also report the same kind of message for iPhone, listing the slot types App Store Connect will accept instead (Dynamic Island large, Face ID large or Dynamic Island medium).
If you are sure the screenshots are uploaded and still see it, developers on the forums suggest checking:
- The language. Screenshots belong to one localization. Pick the language at the top right and check the set is there for the one you are submitting.
- The version. The screenshots need to be on the version you are submitting, not only on an older one.
- Processing. Reload the page and check every image finished processing and is still in the set.
- The size. The iPad set must be at an accepted 13-inch size: 2064 × 2752, 2048 × 2732 portrait.
One developer reported it went away after waiting a day and trying again. If it doesn't, an Apple engineer in that thread asked people to file a report in Feedback Assistant.
Avoiding errors in the first place
- Design at the store size from the start instead of resizing at the end.
- Export as PNG without transparency, or as JPEG, in sRGB.
- Name files in order (1-home.png, 2-search.png) so the set uploads in the order you planned.
- Run the folder through the validator before you open App Store Connect.
Phonepose exports every screen at the exact sizes you pick, as sRGB files with no alpha channel, and checks each file against App Store Connect's rules before you download.