Coperni Sizing: Does It Run Small — And What Size Should You Buy?

By Ella Blake — Fashion Stylist | Tellar Fashion Hub — Always honest, unbiased & unsponsored

Yes — Coperni runs small, and that's almost entirely down to the fact that this Parisian label sizes in French sizing, which sits roughly two UK sizes smaller than you'd expect. So if you're a UK 10, you'll typically need a French 38 (labelled M). Get that wrong and you'll be sending it back before you've even properly admired it. I've made that mistake exactly once — a gorgeous draped top that I was absolutely convinced I could squeeze into. I could not.

Coperni is one of those brands that's been bubbling along on the fashion radar for years — founded in 2013 by Sébastien Meyer and Arnaud Vaillant — but really exploded into mainstream consciousness when Bella Hadid walked the runway and a dress was literally spray-painted onto her body. Since then, the Swipe Bag has become a genuine it-bag, and the ready-to-wear has attracted the kind of quietly cool following that doesn't shout about what they're wearing. If you're looking at a Coperni piece, you already have good taste. The question is just: will it fit?

The Key Sizing Rule: Always Convert to French First

Here's what trips people up: Coperni labels their pieces with French sizes (FR 34, FR 36, FR 38 etc.), but on many retail sites you'll see them listed as XS, S, M — which means nothing without knowing the brand's baseline. The conversion below is your starting point:

FR SizeUK SizeEU SizeUS SizeLabelFR 32UK 4EU 32US 0XXSFR 34UK 6EU 34US 2XSFR 36UK 8EU 36US 4SFR 38UK 10EU 38US 6MFR 40UK 12EU 40US 8M-LFR 42UK 14EU 42US 10LFR 44UK 16EU 44US 12XL

Measurements: What the Numbers Actually Mean

Beyond the conversion table, it's worth knowing the actual centimetre measurements — particularly for Coperni's tailored pieces and dresses, which are cut close to the body. Their sizing is precise and the construction is technical, so there's not a lot of give in the fabric.

FR Size (Label)BustWaistFR 34 (XS)81 cm61 cmFR 36 (S)85 cm65 cmFR 38 (M)89 cm69 cmFR 40 (M-L)94 cm74 cmFR 42 (L)99 cm79 cmFR 44 (XL)104 cm84 cm

If you're between sizes — especially in the bust — I'd always say go up. Coperni's silhouettes are designed to skim, not cling, and sizing down rarely works in your favour with this brand.

Fit by Garment Type

Not everything fits the same way, and Coperni's range is broad enough that it's worth breaking it down:

Dresses & bodysuits: These tend to be the most fitted pieces in the range. If you're fuller in the bust or have a curvier hip-to-waist ratio, sizing up by one FR size is genuinely sensible. The cut assumes a fairly lean frame.
Tops & shirts: Slightly more forgiving depending on the style — draped pieces in particular have more flex. Still, stick to your converted size and don't be tempted to size down for a "fitted" look.
Trousers & skirts: Cut fairly slim in the leg and waist. If you carry more volume in the hips, the French sizing will be less accommodating here. Check the waist measurement against the table above before buying.
Outerwear & jackets: These are slightly roomier by design, so your standard converted size should work well — and they tend to be easier to layer under.
The Swipe Bag: No sizing issues here, obviously — but worth noting that the mini version is genuinely tiny, so don't expect to fit much more than a phone, keys and lip gloss. Ask me how I know.

Is Coperni Worth the Investment?

This is a question only you can answer, but I'll give you my honest take. Coperni isn't cheap — dresses typically start around £400–£600, with outerwear going higher — but the design language is genuinely distinctive. These are pieces that look like nothing else on the high street, and the brand has real fashion credibility (not just hype). If you're building a wardrobe around a few statement pieces rather than lots of fast-fashion buys, a Coperni dress or tailored trouser can do a lot of heavy lifting. It photographs brilliantly, which I know shouldn't matter but absolutely does.

That said, the sizing cut-off at FR 44 (UK 16) is a real limitation, and it's one the brand hasn't addressed. If you're above that, you're unfortunately excluded — which is a genuine gap in the market for a label with this much visibility.

High Street Alternatives with That Coperni Energy

You don't need to spend four figures to get that clean, structural, Parisian-cool aesthetic. These high street and mid-market brands consistently deliver pieces with a similar sensibility:

COS — The closest high street match in terms of architectural silhouettes and minimal construction. Strong on draped tops and sculptural knitwear.
Massimo Dutti — Beautifully made tailoring at a fraction of the designer price. The trousers and blazers in particular have that refined, Parisian edge.
Whistles — Consistently good on structured dresses and sharp outerwear. Great for the grown-up minimalist aesthetic that Coperni does so well.
Reiss — Excellent tailoring, clean lines, and occasion-worthy pieces that hold their own. The occasion dresses are a smart Coperni alternative.
All Saints — For the edgier, more directional side of Coperni's aesthetic — particularly the leather pieces and asymmetric cuts.
Mango — Surprisingly good at sharp, minimal workwear and co-ords right now. The quality-to-price ratio is consistently impressive.
Me&Em — Sophisticated British label with beautifully constructed pieces and thoughtful sizing. Worth knowing for dresses and tailored trousers especially.
Claudie Pierlot — A genuinely Parisian label that sits in a similar aesthetic space to Coperni but at a more accessible price point. The dresses are particularly strong.

Premium & Independent Picks

If you want something a step up from the high street but not quite at Coperni prices:

Paloma Wool — An independent Barcelona-based label with a genuinely original aesthetic. Sculptural knitwear, considered colour palettes, and the kind of pieces that always prompt a "where is that from?" response. Not widely stocked in the UK, but worth seeking out.
Baserange — A Copenhagen-based brand doing incredibly refined, body-conscious basics and minimal separates. The construction quality is excellent and the sizing is far more inclusive than most comparable labels.

Luxury Alternatives if Coperni Is Your Gateway

If Coperni has opened a door to investment dressing, these designer labels are worth exploring next:

The Row — For the most elevated, understated luxury version of the minimal aesthetic.
Totême — Swedish label with beautifully constructed coats, dresses and tailoring that sits just below Coperni in price but with equally strong design credentials.
Jacquemus — Another French label with that same playful-but-precise sensibility, and also uses European sizing — so the same conversion rules apply.

Never Get Coperni Sizing Wrong Again — Use Tellar

The reason Coperni sizing trips people up is the French size conversion — and it's exactly the kind of brand-specific quirk that Tellar.co.uk was built to solve.

Tellar is the UK's leading free sizing tool — no downloads, no subscriptions, no faff. Just enter your measurements once (bust, waist, hips — or your size in a brand you already know fits) and get your precise size across 1,500+ brands instantly.

📏 Measure once — bust, waist, hip, or a brand size you already trust
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Plus, explore the Tellar Fashion Hub — a free library of honest, unsponsored style guides from our team of stylists. No brand deals. No agenda. Just useful fashion advice.

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