Upscaling.

Enlarging a raster image by interpolating new pixels, whether the seller does it, an AI tool does it or the platform does it. It raises the DPI figure without adding detail. DTF Transfers Now puts the arithmetic plainly: a 300 DPI file scaled up to double its size is really a 150 DPI file. Printful tells sellers not to enlarge a small, low-resolution image and expect it to print sharply. Printify enhances low-resolution designs automatically but says designs with artificially increased resolution cannot be detected by its tool, so a seller who upscales first switches the platform's own fix off. Some platforms upscale without asking: Printumo enlarges artwork that falls short of the product size or of its DPI minimums. The complaint arrives as a soft print from a file whose DPI tag said 300.