Eventually, you could come across that the Step&Repeat panel shows the same value in the Offset, Origin and Size fields.

This is due to Photoshop default units being set to Percent, which is actually a ratio and thus has no units. The panel needs a measurable magnitude to set positions and sizes properly and has been developed to support all other units that Photoshop provides, whether these are pixels, picas, points, inches, centimeters or millimeters.

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