DPI vs pixels

DPI stands for dots per inch, a measure from printing. A 2,000 x 2,000 px image saved at 72 dpi and the same image saved at 300 dpi contain exactly the same pixels and look identical on a screen; only the suggested print size differs.

Marketplaces mention DPI, but the rule that matters is pixels. Amazon asks for at least 72 dpi, which almost every file meets, and then sets the real limits in pixels: the longest side between 500 and 10,000 px, with zoom at 1,000 px or more. Amazon's A+ Content guidelines also ask for at least 72 dpi alongside fixed pixel sizes such as 970 x 300. eBay's picture policy says: "Photos must be at least 500 pixels on the longest side." TikTok Shop asks for at least 600 x 600 px, Etsy recommends 2,000 px, and Walmart sets 1,500 x 1,500 px as the minimum for zoom.

The classic mistake is changing 72 dpi to 300 dpi in an editor and expecting a sharper image. Unless the editor also resamples, the pixel count is unchanged and nothing improves. If it does resample upwards, it invents pixels by interpolation, which adds softness, not detail.

Another mistake is briefing a photographer or designer for "300 dpi high-res" files without giving pixel dimensions. Ask for the longest side in pixels per platform instead, for example 2,000 px for Etsy or 2,048 x 2,048 for a square Shopify image.