Sézane was launched in Paris in 2013 by Morgane Sézalory, a designer with no formal training who started in 2008 by selling vintage online under the name Les Composantes, with a blog showing how to style each piece. The brand name is a blend of her first and last names. She has said vintage taught her to care about fabrics, details and quality.

The cardigan people mean is the Gaspard. The brand describes it as made of super kid mohair, baby alpaca and polyamide, with mother of pearl buttons that can be worn at the back or the front. Elle UK wrote that it has "truly earned cult status", and Harper's Bazaar UK lists it among the founder's most popular pieces. So a Sézane cardigan dupe search is really a search for a feeling: a soft knit, a neat row of buttons, a shape that works open, closed, or turned around.

This edit is pieces from other labels that share that idea, in the same spirit, with one extra detail borrowed from the French cardigan playbook: Who What Wear points to "a row of polished gold buttons" as what lifts a basic knit. For October, I would lean on those first.

The Henderson from Petal & Pup is cream, V-neck, chunky ribbed, with hammered gold-tone buttons, and it is the easiest to wear over a white tee. The Toasty from VICI Collection is brown and nubby with organic-shaped buttons, a good partner for a corduroy skirt. The Dakota from Bishop + Young has a bouclé stitch, gold buttons and two small pockets. The Janet rib from Marciano is close-fitting and black, with big shiny buttons that do the talking. Test: fasten every button and check that the placket lies flat and the buttons sit snug in their holes.

Length decides almost everything with a short cardigan. If the hem lands at your waistband, it works with high-waisted denim and with a midi skirt, and nothing bunches. If it lands lower, it reads as a different garment. Check that on yourself, arms down, before you commit.

Chinti & Parker is the name I would go to first, in wool and cashmere. The navy crew neck is finely knit and cropped, and the black one is mid-weight, so it is the better pick for a coat-free October morning. Favorite Daughter's Eleanor in taupe adds chunky cable stitching to a fitted crop, which gives you texture without bulk. Mango's heather gray crop has a classic crewneck and ribbed trim, and the H&M version in dark gray is 100% wool, short and fitted, with covered buttons, so the front stays quiet. Goldie Lewinter's Marina in black is ribbed and close-fitting with round tortoiseshell-look buttons, the one for a slim, simple shape.

Sézalory has said she wants pieces "made to last a lifetime", and that is a decent filter here: look at the ribbed trims and the button band, since those take the most pulling. If the rib springs back when you tug it, good.

What I would skip: a crop in a very lightweight knit if you plan to wear it open over a dress, because it tends to slide off the shoulders.

Mohair is the fiber behind the Sézane original, which the brand makes with super kid mohair and baby alpaca, so this group gets closest on feel. Look at the label first. Several of these list mohair alongside wool and polyamide, and the percentages tell you how fuzzy and how structured the knit will be.

& Other Stories has three here. The off-white button-front is mohair, wool and polyamide, brushed and soft. The dark mole version is cotton, mohair and wool, relaxed with raglan sleeves and a buttoned placket. The gray pointelle adds a tiny open texture. H&M's cropped dark gray cardigan has shoulder pads and offset buttons, a slightly sharper take. Bimba y Lola's long ivory cardigan with contrast trim is straight-cut and loose, and its gray-green openwork style has a plunging V. Vero Alfie's pink Verbena is the playful one, with bobble flowers and a high mohair content. MOTHER's powder pink crop is fuzzy, round-neck, button-front.

Here is a test: brush your hand across the knit and then look at the buttons. A good mohair cardigan should have a button band firm enough to hold the fuzz in place, and buttons that echo the color, like a pearl-effect row.

What I would skip: a pale mohair under a dark top that sheds lint, unless you like a lint roller in your bag.

What matters with a Breton is the stripe width and the neckline. Sézane keeps a Breton stripe sweater on its list of Top Parisian pieces, as Harper's Bazaar noted, so these are the look-alikes to pair with a cardigan on top.

The Chinti & Parker Breton Heart in navy and white has a red heart intarsia and is wool and cashmere. Whistles has a cream cotton knit with wide black stripes and buttons at the shoulder, and Celtic & Co. does a navy and red drop-stitch Breton in slub cotton. Joe's Penelope is a relaxed black and white turtleneck with dropped shoulders. Boden gives you two softer ones: the Marta in pure merino with a sailor collar, camel and navy, and the Lucy, a lightweight cotton in camel and blue. H&M has a white and navy oversized rib with a mock turtleneck, and a short burgundy and white fine-knit with a boat neck.

How I would wear them: under an open cardigan, so the stripes show as a clean column of color. Test: stretch the stripes out flat in the fitting room and check that they meet at the side seams, because stripes that do not match look careless from across a room.

What I would skip: a wide-striped sweater under a heavily textured cardigan. Let one of the two stay quiet.

In a cardigan, cable stitch does the same job the buttons do in the original: it gives a plain shape something to look at. The question is how much. Pick the weight of the cable for the weather you actually have.

Free People's Opal in steel gray is chunky and oversized with tortoiseshell buttons and drop shoulders, so it behaves like a small blanket. EDIKTED's Braiden is ultra-chunky and open at the front, no buttons at all. Princess Polly's Donielle in beige mixes cable with other chunky stitches. For something lighter, Splendid's Brooks is a white cable crew neck with a full button front, Splendid's Rubi in blush pink is a cropped cotton with all-over cable texture, and Point's black twisted cable cardigan has gold-tone buttons. COS makes a gray one in 100% merino with ribbed trims, and Petal & Pup's Nova in cream is longline, with dimensional cables.

Test the cable by pulling it gently sideways. A good cable bounces back and the ridges stay crisp. Then check the buttons, because a cable cardigan lives or dies on whether the buttons sit flat against the raised stitches.

What I would skip: a longline cable cardigan under a short coat, because the hem peeks out and the proportions go odd.

I would begin with the buttons. If the look you want is the Sézane Gaspard feeling, choose a soft knit with a clean row of buttons that you could turn to the back. If you want the French cardigan with gold buttons, go to the Henderson or the Toasty, and fasten the whole front before you decide.

Then pick the length that fits your skirts and your jeans, add one stripe underneath, and leave the rest alone.

Sézalory started with vintage her sister left behind and a good eye. A cardigan is a small version of that: one good thing, worn a hundred ways. If you want to keep browsing, I also put together Cropped Cardigan and The Cardigan as a Top.