Sui Generis Size Guide — Clothing & Shoe Conversions

Two sizes. One item.

Marked size is the size printed on the designer’s tag. US listing size is the comparison used by Sui Generis, a US company, to help our customers shop.

For example, our women’s clothing chart places French 40 alongside US 8 and Italian 44. The item’s original label is unchanged.

A note on tailoring and fit. Luxury garments are often investment pieces and may have been professionally tailored for a previous owner. Alterations to the waist, seams, sleeves or hem can change the fit while the original size tag remains unchanged. Treat the marked size and US size comparison as starting points, and use the item’s current measurements to judge fit. Ask us about any particular measurement before purchasing.

Designers’ sizing evolves. Each designer has a distinct approach to proportion and fit, and that approach can change over the years, between collections and across different lines. The same marked size may fit differently depending on the era and whether a piece was designed to be close-fitting, relaxed or oversized. Use our conversions as a starting point, then consider the intended silhouette, current measurements and any tailoring.

Creative direction can affect sizing. When a new designer takes the helm of a fashion house, the intended silhouette, proportions and fit may change, and sizing guidance may change with them. A current size chart may therefore not describe a piece from an earlier collection or creative era. Where available, consult guidance for the item’s own collection and compare its current measurements, allowing for any tailoring.

Choose the correct clothing or shoe table, find the marked size, then read vertically in the same column to the US row. Compare the item’s measurements with a piece that fits you well. A brand’s own multi-country tag and item-specific fit information take priority over a general table.

Gucci men’s footwear: the half-size comparison

Gucci’s published men’s shoe chart lists the US equivalent half a size above the Gucci size: Gucci 8 = US 8.5; Gucci 9 = US 9.5; Gucci 10 = US 10.5. This explains the half-size note in the Sui Generis reference.

Use the size marked on the shoe and the relevant Gucci chart. This conversion is separate from a particular style’s fit advice, such as a recommendation to size down. Check the model, era and measurements for vintage or unfamiliar pairs.

View Gucci’s official shoe size guide