Fashion e-tailer Zalando SE said on Friday it had bought a body scanning company to help solve the biggest question for people buying clothes online: How do I know if they will fit?

Zalando has acquired Fision, a Zurich-based software company whose body-scanning app includes a virtual dressing room to help buyers easily judge whether a garment will be the right size for them.

The deal, whose terms were not disclosed, should help reduce the amount of clothes sent to buyers that are the wrong size, and in turn mean fewer outfits get sent back.

“Customers will get size advice earlier in their relationship with Zalando," said Stacia Carr, Zalando’s Director of Engineering - Size and Fit.

"At the same time, we can create a feedback loop between brands and consumers designed to drive customer loyalty and in the long run reduce waste.”