What is the sizing difference between women's Jordan 1 and men's Jordan 1?

Women's Jordan 1 is produced on a women's-specific last, which is narrower at the heel and shorter in the toe box relative to the same European size in men's. Women's sizes on KM are listed as women's; there is no need to convert. If you normally wear men's Jordans, go 1.5 sizes down from your men's size for the women's version.

What is the difference between the Jordan 1 High OG, Mid and Low for women?

Jordan 1 High OG uses the full-height collar with premium tumbled leather uppers and numbered Jumpman branding; it carries the highest price and collectibility. Jordan 1 Mid is a daily-wear height with a lower price and a slightly stiffer construction. Jordan 1 Low removes the ankle collar entirely, making it the most comfortable for all-day wear but lowest in heritage standing.

Are the Jordan 1 Mid Valentines Day colourways re-released or one-time drops?

The Jordan 1 Mid Valentines Day 2022 was a limited release and has not been re-released in the same form. Nike occasionally releases new Valentines Day editions under the Jordan 1 Mid name with different colourways. KM lists the 2022 edition specifically; check the product page for availability, as stock is limited and does not restock.