Remove alpha channel from PNG
App Store Connect rejects screenshots and app icons with an alpha channel, even when nothing looks transparent. Drop your PNGs here: we check them, fill any transparency with a colour you pick and save them without alpha. Free, and nothing leaves your browser.
Before and after: the checkered side shows what is transparent now.
Run the free App Review check before you submit: it catches metadata, privacy and screenshot problems that get apps rejected.
Frequently asked questions
Why does App Store Connect say my image has an alpha channel?
PNG files can store a fourth channel for transparency. App Store Connect refuses screenshots and the 1024 × 1024 app icon that have one, even if every pixel is opaque. Exports from Figma, Sketch, Photoshop and the iOS Simulator often include it.
How do I remove the alpha channel?
Drop the PNG on this page and download it again. Transparent areas are filled with the background colour you choose, and the file is saved as an RGB PNG (or JPEG) without an alpha channel. The size stays the same.
Will the image look different?
Only areas that were transparent change: they take the background colour. Fully opaque images look exactly the same.
PNG or JPEG?
Both are accepted. PNG without alpha keeps text and UI perfectly sharp; JPEG files are smaller. App icons should be PNG.
Is my image uploaded?
No. Your browser checks and converts the files on your device; nothing is sent to a server.
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