Transparent Background Checker

Upload any image to check whether it actually contains transparent pixels - Not just whether the format supports transparency.

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Drop an image here or click to select

PNG, WebP, GIF, JPG - Up to 15 MB

Preview on checkerboard

Format
Color mode
Dimensions
Alpha channel
Transparent pixels
Note: The file has an alpha channel reserved for transparency but all pixels are currently fully opaque. If you intend to use transparency, you'll need to erase or delete parts of the image in GIMP or another editor.
Want transparency? Convert this image to PNG or WebP and add an alpha channel. In GIMP: Image → Flatten Image, then Layer → Transparency → Add Alpha Channel.

How Transparency Actually Works

Just because an image is a PNG or WebP doesn't mean it has transparent pixels. Transparency requires two things: an alpha channel (the format must support it), and at least one pixel with an alpha value below 255.

FormatAlpha Channel?Notes
PNGYes (optional)Most common format for transparent images
WebPYes (optional)Supports both lossless and lossy with alpha
GIF1-bit onlyPixels are either fully transparent or fully opaque
JPEGNoCannot store transparency - White background is added on export

What Alpha Values Mean

Alpha ranges from 0 (fully transparent) to 255 (fully opaque). Values in between create semi-transparency - Useful for soft edges, shadows, and anti-aliased text.

Adding or Removing Transparency in GIMP

To add an alpha channel: Go to Layer → Transparency → Add Alpha Channel. Now you can erase to transparent, or use Colors → Color to Alpha to remove a background color.

To remove transparency (flatten): Go to Image → Flatten Image. GIMP will fill transparent areas with the background color (usually white).

Always export as PNG (not JPG) to preserve transparency. Use File → Export As and choose .png.