Push-up Bikini Swimsuit with Floral Design

Bikini Size Guide: How to Measure for the Perfect Fit

Your regular clothing size won't tell you much here — bikini sizing runs on three measurements (bust, waist, hips) and shifts style to style. Here's how to measure yourself in under five minutes, pick between two sizes when you're stuck, and check that a suit actually fits before you take the tags off.

Quick Answer

Measure your bust (fullest point, tape level), underbust (directly under the bust, snug), waist (natural crease, not your belly button), and hips (fullest part of your seat, not just your hip bones). Match those numbers to the size chart on the specific product page — not a generic size guide — since coverage and stretch vary by style.

What You'll Need

• A soft measuring tape
• A mirror
• A non-padded bra or thin, fitted clothing
• Somewhere to jot down the numbers

Keep the tape level and snug against your skin, not squeezing it. Measure twice — numbers drift more than people expect.

How to Measure

One note on tops sold by bra size: follow the bra-size chart the brand gives you for that product. Don't add inches to your underbust measurement unless the brand's instructions say to — that's a rule of thumb people misapply constantly.

Reading a Size Chart

A size chart shows the body measurements a size is built for — not the flat measurements of the garment. Swimwear stretches, so the suit will look smaller laid flat than it fits on your body.

Use the chart on the individual product every time. A medium in one style is not a medium in another.

• Top: prioritize bust, then underbust
• Bottom: prioritize hip, then waist (especially for high-rise cuts)

When Your Top and Bottom Are Different Sizes

Completely normal — plenty of people size up on one piece and down on the other. If the suit is sold as separates, size each piece independently.

If it's only sold as a matched set, size for whichever piece has the least adjustability:

• Bust runs medium, hips run large → go with the large; a top with adjustable ties is more forgiving than a fixed waistband.
• Bottom has adjustable side ties → it'll absorb a wider hip range than the numbers suggest.

Let the construction of that specific suit decide, not a blanket "always size up" rule.

Stuck Between Two Sizes?

Size up if:

• You want more coverage or comfort
• The waistband or back closure is fixed, not adjustable
• Your bust or hip measurement sits at the top of the smaller range
• The listing says the style runs small
• You're fuller-busted and the top has minimal adjustment

Size down if:

• Most of your measurements land within the smaller range
• The fabric has generous stretch
• Both pieces are highly adjustable
• You prefer a snug fit and the smaller size doesn't dig in

Don't size down just because swimwear stretches — a suit that's genuinely too small will dig in, flatten your bust, cut coverage, and shift the moment you move.

How It Should Actually Fit

Top:

• Band stays level, doesn't ride up
• Cups/fabric fully contain your bust — no spillage
• Straps stay put without cutting into your shoulders
• Underwire sits around the tissue, not on top of it
• You can raise your arms without the whole thing shifting

Too small: spillage, a band that hurts, underwire pressing on tissue, straps digging in, center pulling away from your body.

Too large: gaping cups, a band riding up your back, straps that won't stay adjusted, no support even after you tighten everything.

Bottom:

• Lies flat at the waist and leg openings
• Matches the coverage shown in the product photos
• No sagging or wrinkling across the seat
• Stays put when you walk or sit

Too small: digs in at the waistband or leg openings, less coverage than shown, rolls or bunches.

Too large: sags or wrinkles at the seat, gaps at the waistband, gets noticeably looser wet.

Fit Notes by Style

• Triangle tops — usually adjustable at neck and back; check the triangles give real bust coverage without overtightening the band.
• Bandeau tops — no straps, so the band does all the work. Too loose and it slides; too small and it compresses.
• Halter tops — the neck tie shouldn't be doing all the lifting. If your neck hurts, the band needs adjusting, not the tie.
• Underwire tops — go by both bust and underbust. The wire should surround the tissue and sit flat against your ribs, not pinch.
• High-waisted bottoms — check waist and hip both; if they're different sizes, follow whichever measurement the design adjusts least.
• Side-tie bottoms — flexible at the hip, but the ties won't change front/back coverage.
• Cheeky/thong bottoms — built for less back coverage by design. Sizing up adds comfort, not coverage.

Test It Before You Commit

With tags and liner still attached, try:

• Raising both arms overhead
• Sitting down
• Bending forward
• Twisting side to side
• Walking a few steps
• Adjusting straps back into place

If it stays put without digging in, gaping, or needing constant readjustment, you've got the right size. Keep tags and liners on until you're sure — most swimwear returns hinge on it.

FAQ

Should you size up or down in a bikini? Go by the product's own size chart, not a universal rule. Size up if your key measurement is at the top of the smaller range or you want more comfort; size down only if your measurements land comfortably within the smaller range and the fit stays secure.

Are bikini sizes the same as clothing sizes? Not reliably — swimwear sizing varies by brand and style. Treat your regular size as a starting point; your bust, waist, and hip measurements are the real reference.

Should a swimsuit feel tight when dry? Close to the body, yes — painful or breath-restricting, no. It also needs to stay secure once wet, which is a different test than how it feels dry.

What measurement matters most for bottoms? Hips, generally. Add waist to the equation for high-waisted styles.

What measurement matters most for tops? Full bust for letter-sized tops; add underbust if the top has underwire, a fitted band, or a fixed closure.

Can I wear different sizes on top and bottom? Yes — very common. If they're sold as separates, size each one on its own measurements.

How do I know if a bikini runs small? Check that specific product's chart, fit notes, fabric content, and reviews. Don't assume consistent sizing across a store's whole swim lineup.

Easy returns — store credit only

Approved returns are issued as store credit (gift card). We do not refund to your original payment method.

Return coverage

Add return protection at checkout to waive the U.S. return label fee on eligible items.

Return window

Eligible items can be returned within 30 days of delivery.

Processing

Store credit is emailed within 2–3 business days after we receive and approve your return.

Return conditions

Items must be unworn, unused, and in original condition with all tags attached.

Return label fee

U.S. returns: $6.99 unless return protection was purchased at checkout.

Reorder instead of exchange

We do not offer direct exchanges. Return for store credit, then place a new order.

Non-returnable

Final sale items, and personalized or made-to-order pieces (e.g., name-engraved necklaces, made-to-order skirts).

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