Women's Swimwear & Beachwear Guide: Finding Your Best Fit

A great swimsuit comes down to three things: the style you choose, how it fits your shape, and the fabric behind it. One pieces give the most coverage and support, bikinis offer the most flexibility to mix and match, and tankinis sit comfortably in between. Matching one of these to your body shape and the way you actually spend your day at the beach or pool is the fastest way to find a suit you will not want to take off.

Shopping for swimwear can feel more complicated than it should be. There are one pieces, bikinis, tankinis, high waisted bottoms, underwire tops, and a dozen cuts in between, and it is easy to end up overwhelmed before you have even tried anything on. This guide walks through the main styles, where they came from, how to match them to your body shape, and what to look for in fabric and fit. We will also cover a few well known brands worth knowing before you buy.

One Piece Swimsuits: The Original Silhouette

The one piece has been the foundation of women's swimwear for well over a century. Much of that history traces back to Annette Kellerman, an Australian competitive swimmer born in Sydney in 1886, who caused a public sensation in 1907 for wearing a fitted, men's style unitard swimsuit on a Boston beach at a time when women were expected to swim in heavy wool dresses and stockings. The controversy helped shift public opinion, and by the 1912 Olympics women were competing in shorter, more practical one piece suits. In the United States, the term swim suit itself was coined in 1915 by Jantzen Knitting Mills, a swimwear manufacturer that helped popularise the modern, more form fitting knitted style.

Today's one piece has moved a long way from wool and stockings. Modern versions range from simple, supportive training suits to plunging, cut out and belted styles designed as much for the beach as the pool. A well fitted one piece gives full coverage and support without any straps to adjust, which is why it remains the most popular choice for swimming laps, chasing kids around a pool, or simply wanting one less thing to think about at the beach.

Bikinis: From Scandal to Wardrobe Staple

The bikini has one of fashion's more dramatic origin stories. It was created in 1946 by French designer Louis Réard, who named it after Bikini Atoll in the Pacific, where nuclear weapons testing had recently taken place, reportedly because he expected his design to cause an equally explosive reaction. He was not the only one working on a minimal two piece that year. Fellow French designer Jacques Heim had released a two piece called the Atome only weeks earlier and billed it as the smallest swimsuit in the world, but Réard's design used even less fabric and was the first to expose the navel, which was considered scandalous at the time. It took more than a decade before bikinis were widely accepted on beaches, and today the two piece bikini is the most flexible swimwear style on the market, since separates let you mix and match top and bottom sizes rather than being locked into one fixed fit.

Bikini styles today go well beyond the classic triangle top. Bandeau tops offer a strapless look, halter and underwire styles add support for a larger bust, and high waisted or high cut bottoms adjust how much coverage you get through the hip and leg. If you like the flexibility of separates but want a bit more support built in, our guide covering padded and enhancing swimwear explains how structured cups and light padding work without looking obvious.

Tankinis: The Best of Both Worlds

The tankini was invented in 1998 by American swimwear designer Anne Cole, who ran her family's California swimwear label and wanted to close a gap she saw in the market between the coverage of a one piece and the flexibility of a bikini. Her design paired a tank style top, cut from swimsuit fabric, with standard bikini bottoms, giving women more coverage through the midsection while keeping the convenience of a two piece. Within a few years it had captured a large share of the swimwear market, and variations like the camisole style camkini and the strapless bandeaukini followed soon after.

Tankinis remain a popular middle ground today, particularly for anyone who wants more tummy coverage than a bikini but does not want the single fixed silhouette of a one piece. They also make bathroom breaks considerably easier than a one piece, which is part of why they became such a hit with mothers and swimmers of all ages when they first launched.

Finding Your Best Fit by Body Shape

There is no single correct swimsuit for any body, and the most flattering suit is always the one that makes you feel comfortable and confident. That said, a few general style principles can help narrow down where to start.

• Hourglass: With a balanced bust and hips and a defined waist, high waisted bikinis, belted one pieces, or styles with waist detailing tend to highlight your natural shape.

• Pear: With hips wider than the shoulders, a bright or detailed top paired with a simple, darker bottom helps balance proportions. Halter necks and bandeau styles can also draw the eye upward.

• Apple: With more fullness through the midsection, a tankini or a one piece with ruching or draping around the stomach offers support and a smoother silhouette, while a deeper neckline helps elongate the torso.

• Rectangle: With similar measurements through the bust, waist and hips, ruffles, prints, or a cut out one piece can help create the impression of more curves.

• Inverted triangle: With broader shoulders and a smaller lower body, a plainer top paired with a bolder, more detailed bottom helps bring balance to the overall look.

If you want a deeper dive into matching cuts to your shape, our full swimwear for body type guide goes through each shape in more detail.

Support, Underwire & Bust Sizing

For anyone with a fuller bust, bikini and swimsuit tops that offer real support make a noticeable difference to comfort. Underwire tops, moulded cups, and wider set straps all help distribute weight more evenly, in much the same way a well fitted bra does. In fact, several swimwear brands now size their tops using standard bra sizing, such as 10D or 12E, rather than the generic small, medium and large scale used for basic bikini tops. If bra sizing is new to you, our women's lingerie and bra fitting guide is a useful starting point, since the same measuring principles carry across into swimwear.

A Quick Guide to Swimwear Fabric

Whatever style you choose, the fabric underneath does most of the practical work. The main players are nylon, polyester and spandex.

• Nylon is soft, lightweight and comfortable, but it breaks down faster with regular chlorine exposure, making it better suited to beach days and occasional swims than daily laps.

• Polyester is more durable and genuinely chlorine resistant, holding its colour and shape through repeated pool sessions, though it is slightly less stretchy than nylon.

• Spandex, also known as elastane or Lycra, is rarely used alone but is blended in at around 10 to 20 percent to give swimwear its stretch and recovery.

Many higher end suits also use PBT, a stretchy, chlorine resistant polyester variant popular in both competition and premium recreational swimwear. If you swim regularly, a polyester or polyester PBT blend will outlast a plain nylon spandex suit by a wide margin, and our swimwear fabric guide runs through the full comparison.

Sun protection is worth considering too. Swimwear sold in Australia is sometimes tested against the AS/NZS 4399 sun protective clothing standard and given an Ultraviolet Protection Factor rating, with 50+ marking the highest level of protection available. It is a useful detail to check if you spend long days outdoors rather than mostly in the water.

Getting the Sizing Right

Swimwear sizing varies more between brands than almost any other clothing category, so a size 10 in one label can fit quite differently to a size 10 in another. It pays to measure your bust, waist and hip with a soft tape measure and compare those numbers against the specific brand's chart rather than assuming your usual size will carry across. Our full guide on how underwear and lingerie sizing works explains why sizing differs so much between brands and how to measure yourself accurately at home.

Plus Size Swimwear Options

Plus size swimwear has also come a long way from the limited, control focused options of years past. Good plus size ranges now offer the same variety of one pieces, bikinis and tankinis as standard ranges, with construction details such as reinforced seams, wider straps and built in support designed specifically for larger bodies rather than simply resized versions of smaller styles. Our plus size swimwear guide has more detail on what to look for.

Best Women's Swimwear Brands to Know

A handful of brands have shaped women's swimwear as it exists today, and each tends to specialise in a slightly different niche:

• Speedo: The Australian brand behind decades of competitive swimwear innovation, still the benchmark choice for serious lap swimmers and training suits.

• Seafolly: Founded in Sydney in 1975 by Peter and Yvonne Halas, Seafolly built its name on bright, beach inspired prints and has grown into one of the most recognised swimwear labels in the world, with stores across Australia, the United States and Singapore.

• Jets: An Australian label operating since the 1970s and relaunched in 2001 by Jessika and Adrian Allen, Jets is known for its structured, figure flattering cuts and premium finishes.

• Anne Cole: The American label behind the invention of the tankini in 1998, still a go to name for anyone after a supportive, two piece alternative to a full one piece.

If you would like to browse current styles across several of these labels in one place, our women's swimwear collection is worth a look before you decide.

Caring for Your Swimwear

Good swimwear lasts far longer with a small amount of care. Rinse it in cold water straight after every wear to remove chlorine, salt and sunscreen residue, then hand wash it in a mild detergent rather than putting it through the washing machine, which can stretch delicate fabric and damage embellishments. Skip the tumble dryer altogether, since heat is one of the fastest ways to break down elastane and fade colour. Instead, gently press out excess water, lay the suit flat in the shade, and let it air dry naturally.

Wearing Swimwear Beyond the Beach

Simple one pieces and bikini separates have become genuinely versatile in recent years, doubling as bodysuits, crop tops and high waisted bottoms worn under skirts or trousers well away from the pool. It is a trend that works best with plainer, less overtly beach specific cuts rather than heavily embellished or sheer styles, which tend to read as swimwear wherever you wear them. If you are curious about which of your pieces could pull double duty as everyday clothing, our guide on wearing swimwear as everyday clothing covers exactly where that line sits.

Frequently Asked Questions

What is the most flattering swimsuit style for most body types?

There is no single style that suits everyone, since body shapes vary so much, but a well fitted one piece with some waist definition or a high waisted bikini tends to work well across a wide range of shapes because it balances the bust, waist and hips rather than emphasising just one area.

What is the difference between a tankini and a one piece?

A tankini is a two piece suit with a tank style top and separate bikini bottoms, offering more coverage than a bikini while still being two separate pieces. A one piece is a single connected garment. Tankinis are generally easier to get in and out of, while one pieces offer a more streamlined, secure fit for swimming laps.

How do I know what size swimwear to buy?

Always check the specific brand's size chart rather than relying on your usual clothing size, since fit varies noticeably between labels. Measuring your bust, waist and hip with a soft tape measure, then comparing those numbers to the brand's chart, is the most reliable way to get it right the first time.

What fabric lasts longest in a chlorinated pool?

Polyester and polyester PBT blends are the most chlorine resistant options and will outlast a plain nylon spandex suit if you swim regularly. Nylon spandex blends are softer and more comfortable but suit occasional swims better than daily pool sessions.

Is modest swimwear only for religious reasons?

No. While modest swimwear is worn for religious and cultural reasons by many women, it is also chosen for sun protection, comfort, personal style, or simply a preference for more coverage, and has become a mainstream category stocked by most major swimwear brands.

Whichever style you land on, the goal is the same: something that fits properly, suits how you actually spend your time by the water, and holds up to salt, sun and chlorine. For the full picture across men's and women's styles, fabrics and fit, head back to our complete swimwear style guide, or go ahead and shop women's swimwear to find your next favourite.