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Auto-trim

remove transparent edges · tight bounding box

Drop PNGs with transparent borders and the tool finds the tight bounding box around opaque pixels and crops to it. Perfect after compositing in another tool, or for trimming exported assets that came with extra padding.

Drop PNG files here

Multiple files allowed

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    Ready.

    When to use this tool

    Anytime an image has unnecessary transparent space around its content — exported icons, signatures, sprite frames, screenshots saved with extra canvas. Auto-trim finds the rectangle of actual pixels and discards the rest.

    Threshold

    The threshold controls how transparent a pixel must be to be considered "empty." 0 (default) means any non-zero alpha counts. Bump it up if your image has faint edge anti-aliasing pixels you also want to trim.

    Use cases

    FAQ

    What if my image is fully opaque?

    Nothing changes — the bounding box is the whole image. The output is the same dimensions as the input.

    What if my image is fully transparent?

    The tool reports "all transparent — nothing to trim" and skips that file.

    Does it preserve the actual content?

    Yes — only fully-transparent (or below-threshold) edge pixels are dropped. Interior content is unchanged.