“The dimensions of one or more screenshots are wrong”: the fix

App Store Connect checks your file against a closed list of pixel sizes. One pixel off and the upload stops. Here is the list, slot by slot, and the usual ways to land outside it.

Published: 5 September 2026 · Last reviewed: 1 November 2026

Accepted sizes, slot by slot

Find the slot you are uploading into, then check your file against the sizes in its row. Portrait sizes are listed; landscape is the same numbers reversed.

Older slots follow the same rule: the 5.5″ slot takes 1242 × 2208 and the 4.7″ slot 750 × 1334. Every value above was read from Apple's own screenshot specifications on 1 September 2026 and checked again on 12 October 2026: no size had changed, though Apple now names these classes by screen type rather than by diagonal. The whole list, for every device, is in the App Store screenshot sizes guide and the screenshot size calculator.

The check is exact, and that is the whole story

The error text is unhelpful because it describes a symptom, not a cause. What happens underneath is simple: every upload slot has a short list of accepted pixel dimensions, and your file either matches one of them exactly or it does not. There is no tolerance, no nearest match, no automatic crop.

So the fix is never to re-export « bigger » or « in better quality ». It is to find which number you are meant to hit and hit it exactly. A real case: 1290 × 2790 fails, 1290 × 2796 passes, and the only difference is six pixels of height.

Which slot is failing?

The error belongs to the set of one display class, so the first question is which class you were uploading into. Work through it in this order:

1. Read each file's real size. On a Mac, run sips -g pixelWidth -g pixelHeight shot.png and compare the two numbers with the row of the slot above. Do not trust the size your design tool displays: it may show points or a rounded frame.
2. Match the file to the slot. A file that is valid for one class is wrong for the next. 1290 × 2796 belongs in the 6.9″ slot; sent to the 6.5″ slot, which takes 1284 × 2778 and 1242 × 2688, it fails.
3. Never send the same file into two classes. One file can only match one row of the table. If you upload a set to several classes, each set needs its own export.

The three ways people land outside the list

The wrong slot. By far the most common. A file sized for the 6.5″ class (1284 × 2778) is dropped into the 6.9″ slot, which does not accept it. The file is perfectly valid; it is simply in the wrong place.

A size that looks right. 1080 × 1920 is a familiar number from video, and it is not on any iPhone list. 1290 × 2790 is six pixels short of a real size, which is what happens when a design tool rounds a frame.

An upscale. Enlarging a smaller capture to reach the target number technically passes the dimension check and fails everything else: the result is soft, and reviewers see it at full size.

The second frequent cause: an alpha channel

A file can have the right pixel size and still be refused. Apple's specifications say it plainly: “Images can't include alpha channels or transparencies.” A screenshot taken in the Xcode Simulator with xcrun simctl io <device> screenshot --type=png is a PNG with an alpha channel even when every pixel is opaque, on every device we checked. The fix is to flatten it, for instance with sips -s format jpeg -s formatOptions 95 in.png --out out.jpg, and to check the result with sips -g hasAlpha out.jpg.

What to do instead

Export at the device's native resolution rather than resizing afterwards. A screen that is 393 × 852 points at @3× is 1179 × 2556 pixels by multiplication, not by scaling: the file comes out of the render at the right size, and there is nothing to correct. The points-to-pixels arithmetic for every model is in iPhone screen sizes in points and pixels, and the resolution rules in App Store screenshot resolution.

If you only intend to upload one iPhone set, it has to be the one Apple requires since October 2026: the 6.3″ class (“iPhone with Dynamic Island (medium display)”), 1206 × 2622 or 1179 × 2556. Apple scales it down for the smaller classes; the 6.9″ and 6.5″ slots fall back only on each other.

Questions

Why does App Store Connect say my screenshot dimensions are wrong?

Because it compares your file against an exact allow-list of pixel sizes for the display class you are uploading into. It is not a range and there is no nearest match: the file matches one of the accepted sizes exactly, or the upload stops.

Can I just export at a higher resolution to fix it?

No. A bigger file is not a closer match: it is simply a different size that is also not on the list. The fix is to find the exact number for the slot you are uploading into and hit it.

Can I crop a screenshot to fit?

Not as a fix. A crop throws away part of the design and only passes if the result lands exactly on an accepted size. Render or export the design at the accepted size instead.

Why does it work for iPhone but not iPad?

The two families have separate lists. A 1290 × 2796 file is accepted in the iPhone 6.9-inch slot and is on no iPad list: the iPad 13-inch slot takes 2064 × 2752 or 2048 × 2732.

Does the error mean my screenshot was rejected by review?

No. This one happens mechanically at upload, before a human sees anything. Editorial rejections come later and read differently.

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