What Is Sizing Like at Calvin Klein?

Calvin Klein generally fits true to size. Buy your usual size across most of the ready-to-wear and you'll be right — but CK runs three fits, so the fit name on the label matters far more than the number next to it. Get that part right and the rest looks after itself.

The short version

Shirts, tees and knitwear: true to size. Choose the fit before you worry about the size.
The three fits: Classic (room through chest and waist), Slim (tapered and close), and Ultra Slim (very trim — for genuinely lean builds).
Tailoring and blazers: a modern cut in slim or classic. The slim really is slim; broader chests and shoulders should default to classic.
Denim: Straight, Slim and Ultra Slim. The waist is honest — the leg taper is the decision to get right.
Underwear: true to size, but the cotton stretches across the day, so cotton-heavy trunks can drop half a size after a few wears. The modal and performance fabrics hold their shape — buy those spot-on.

Early in my styling career I put a client into CK cotton trunks a size up "for comfort." By week two he was swimming in them. The lesson stuck: with CK cotton, trust the chart; with the modal and performance ranges, trust it completely.

How to buy it right

Shirts: neck and chest are your anchors. Go Slim for the true CK silhouette; go Classic if you layer or carry a bit more through the middle.
Denim: take your true waist and choose the leg. Slim suits most men; save Ultra Slim for lean thighs.
Blazers: always buy to the shoulder and have the waist taken in if needed — never the other way round.

How to style it now

CK is minimalist, all-American and quiet — so lean into that rather than fighting it. A stone or navy overshirt, straight-leg indigo denim, a clean white tee and low-key leather trainers or loafers is the CK formula, and it always reads considered. Tonal, monochrome dressing is having a real moment, and CK's muted palette is built for exactly that.

Brands worth knowing at every level

HIGH STREET

Uniqlo — the best-value minimalist basics going. The Supima tees and Smart Ankle trousers rival CK's everyday pieces for a fraction of the price.
Marks & Spencer — underrated tailoring and knitwear with dependable sizing. A strong shout for classic-fit shirts if CK's slim cut runs tight on you.
Charles Tyrwhitt — if CK dress shirts feel narrow, Tyrwhitt's non-iron shirts come in genuinely distinct fits, from classic to extra slim, with proper separate collar sizing.

INDEPENDENT & BOUTIQUE

Sunspel — the T-shirt CK's campaigns wish they made. Superb long-staple cotton and an honest, true-to-size cut.
Percival — a playful British label for knitted polos and overshirts when you want the minimalist base with a touch of character.
Oliver Spencer — relaxed British tailoring and workwear-leaning shirts, cut a shade roomier than CK slim if you prefer breathing space.

DESIGNER & LUXURY

A.P.C. — the French minimalist benchmark. Raw denim and clean crews that share CK's quiet DNA with better fabric and a slimmer European cut — size up if you're between.
Paul Smith — British tailoring with wit. Slim, precise and true to size, for when you want CK's polish with more personality.
Theory — modern-tailoring specialists. Stretch suiting and knits that sit close and clean, ideal if CK Slim is already your fit.

Never guess your size again

Even "true to size" only gets you so far when every brand cuts differently. Tellar.co.uk is the UK's leading sizing tool — it matches your body to over 1,500 brands instantly, so you never have to read a size guide again.

Measure once — chest, waist, hip, or just enter a brand size you already own.
Use the Store Size Lookup to get your exact size in any label — COS, Reiss, Everlane, Arket and more.
Shop with confidence: fewer returns, better-fitting buys.
Always free, no download needed — it works straight in your browser.

Get your Calvin Klein size in seconds:

Store Size Lookup How to Measure

And the Tellar Fashion Hub is a free library of honest, unbiased, independent style guides from our stylists — top picks, best brands and real advice, always free.

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