Bikini & Swimsuit Top Size Calculator
Convert your bra size to the perfect bikini or swimsuit top. Get accurate sizing for every swimwear style, from triangle tops to underwire bikinis.
Calcolatore della taglia del reggiseno
Modalità avanzata (metodo ABTF)
Inserisci sottoseno aderente/tirato e busto in piedi/inclinato/sdraiato per ottenere un elenco di prova e consigli di stile.
Guida alle misure
Misura della banda
Misura attorno al torace, appena sotto il seno. Il metro deve essere aderente ma non stringere.
Misura del busto
Misura la parte più piena del seno tenendo il metro parallelo al pavimento.
Bra Size vs Swimwear Size
Swimwear sizing is not the same as bra sizing. Understanding the difference between cup-sized, S/M/L, and dress-size swimwear will help you find the perfect fit.
Cup-Sized Swimwear
These tops match your bra size (e.g., 34C, 36D). Best for fuller busts. Brands like Freya, Panache, and Bravissimo offer cup-sized options with underwire support.
S/M/L Sizing
Generic sizing based on band and bust range. A size medium typically fits 34-36 band, A-C cup. Less precise but more widely available in standard stores.
Dress-Size Swimwear
Some brands use dress sizes (6-20) for one-piece suits and tankinis. These consider full body measurements rather than just bust, great for matching top and bottom.
Swimwear Sizing by Style
Triangle Tops
Best for A-C cups. Sizing is adjustable via neck and back ties. For larger busts, look for padded triangle tops with wider straps.
Underwire Tops
Best for C-DD+ cups. Provides the most support and shape. Choose cup-sized underwire tops for the most accurate fit.
Halter Tops
Good for B-D cups. The neck tie provides lift and adjustability. For larger busts, look for halter tops with wider underband support.
Sport Swim Tops
Designed for active use. Compression-style with secure closures. Best for A-D cups during swimming, surfing, or beach sports.
Bandeau Tops
Best for A-B cups or as fashion pieces. Minimal support. Look for bandeaus with silicone grip strips and detachable straps for more versatility.
Water Fit Adjustment
Swimwear behaves differently when wet. Most nylon-spandex blends can stretch up to half a size when saturated, which means a snug fit when dry often becomes a perfect fit in the water.
Chlorine and salt water can also affect fabric elasticity over time. If you plan to wear your swimsuit frequently, consider a slightly firmer fit when trying on dry to account for gradual stretch.
Pro Tip: If between sizes, choose the smaller size for swimwear. It will loosen slightly when wet and you won't risk it slipping in the water.
Bikini & Swimsuit FAQ
Should I buy swimwear in my exact bra size?
Not always. While cup-sized swimwear brands match your bra size, many swimwear lines use S/M/L sizing or dress sizes. A 34C bra might translate to a medium or size 6-8 bikini top, depending on the brand and style.
Do swimsuit tops stretch out in water?
Yes, most swimwear fabrics stretch when wet. Nylon-spandex blends can stretch up to half a size larger when saturated, which is why many women prefer a snug fit when dry.
What style works best for larger busts?
Underwire bikini tops and halter necks with sturdy straps provide the best support for larger busts. Look for tops with wider side bands, adjustable straps, and built-in cups or underwire for maximum support.
How do I measure for a bikini top?
Measure your underbust (snug around your ribcage) and your bust at the fullest point, just like measuring for a bra. Use these measurements with our calculator to determine your bra size, then use the size conversion guide for swimwear.
Ready for the Beach?
Use our main bra calculator to find your exact size, then check our swimwear guide for the perfect beach look.
Go to Bra Size CalculatorI nostri contenuti sono ricercati, scritti e aggiornati regolarmente dal nostro team editoriale utilizzando la metodologia A Bra That Fits (ABTF) — lo stesso approccio convalidato dalla community r/ABraThatFits di oltre 500.000 membri. Citiamo ricerca peer-reviewed, standard dell'industria della lingerie e dati della community. I nostri calcolatori elaborano i dati localmente nel tuo browser; non raccogliamo misure corporee.
Utilizziamo il metodo ABTF moderno a 6 misurazioni invece della obsoleta regola dei +4 pollici. Questo approccio è stato convalidato indipendentemente dalla community r/ABraThatFits per produrre taglie di reggiseno più accurate e confortevoli rispetto ai metodi tradizionali a due misurazioni.