So the brand will have discount their inventory, or worse, throw them away. Unspun—founded in 2015 by Stanford alums Beth Esponnette, Walden Lam, and Kevin Martin—wants to transform the system.

That’s the goal of denim unspun, an apparel startup that uses a 3-D body scanner to generate virtual customer avatars made up of 100,000 data points to produce custom-fit jeans. After being ...