What is an H cup size?
An H cup means two different volumes depending on where the brand is from. In UK sizing, H is an 11-inch bust-to-underbust difference — five letters above DD on the ladder D, DD, E, F, FF, G, GG, H. In US sizing, "H" usually labels an 8 to 9-inch difference — the volume UK sizing calls FF or G. That is a two-cup gap behind one letter. EU sizing labels the 11-inch differential K. At H, the letter on the tag has stopped being a reliable signal — the differential in inches is the only consistent reference.
This guide fixes that. It defines both H conventions precisely, shows how to tell within seconds which one a brand uses, maps H across all six major sizing systems, covers sister sizes and the HH step above, and sets out the construction that actually holds at this cup — plus the bands, sports and swim realities that matter at H specifically. The free calculator returns your size in every system at once.
H Cup Bras at HauteFlair
Structured full-bust styles graded for H — full-coverage underwire, side-support, balconette and encapsulation sports bras across bands 30 to 44.
Shop H Cup Bras →Verify Your Size →- UK H = 11-inch bust-to-underbust difference. US H = 8–9 inch — the volume UK calls FF or G.
- The two are two cup sizes apart behind the same letter.
- EU labels the 11-inch differential K; the 9-inch I.
- Quick test: if a brand's chart lists FF and GG, its H is 11 inches.
- Sister sizes for a UK 34H: 32HH and 36GG — same cup, different band.
- A UK 34H holds roughly 1,020 mL per breast, weighing about 2.2 lb.
- H is band-heavy: 38H through 44H are among the most-searched H sizes.
- Full-bust construction is mandatory — side support, wide wires, firm bands, three-piece cups.
UK H vs US H — The Two-Cup Gap
This is the single most important thing to understand about H cup, and it costs shoppers more money than any other sizing quirk.
The UK ladder runs D, DD, E, F, FF, G, GG, H — with FF and GG as full steps. Counting from DD at 5 inches, that puts UK H at 11 inches. Most premium full-bust brands use this ladder.
The US convention typically skips those double-letter steps and reaches H sooner. In most US-labelled ranges, H sits at 8 to 9 inches — the volume the UK calls FF or G. Which of the two depends on whether that brand includes a DDDD step. Some US brands write the same volume as DDDD rather than H.
| Differential | UK (with FF/GG) | US | EU |
|---|---|---|---|
| 8 inches | FF | G / H | H |
| 9 inches | G | H / DDDD | I |
| 10 inches | GG | I | J |
| 11 inches | H | J | K |
Open the brand's size chart and look for FF and GG. If both appear as steps, that brand's H is an 11-inch differential — the UK convention. If the chart jumps DD → DDD → DDDD → G → H, its H is roughly 8 to 9 inches, and what it calls H is what full-bust brands call FF or G. Two seconds of checking prevents a two-cup error.
Someone who measures an 11-inch differential, correctly identifies as a UK H, and then orders a US-labelled H arrives two to three cups too small — because that brand's H is an 8 to 9-inch cup. The reverse also happens: a US H wearer ordering a UK H ends up two cups too large. Measure once, record your differential in inches, and shop by the number rather than the letter whenever you cross brands.
What Is an H Cup Equivalent To?
Because the label is unreliable, "equivalent" questions are among the most-searched H cup queries. Here are the direct answers, based on an 11-inch differential (UK H).
| Your UK size | US equivalent | EU | Sister down | Sister up |
|---|---|---|---|---|
| 32H | 32J | 70K | 30HH | 34GG |
| 34H | 34J | 75K | 32HH | 36GG |
| 36H | 36J | 80K | 34HH | 38GG |
| 38H | 38J | 85K | 36HH | 40GG |
| 40H | 40J | 90K | 38HH | 42GG |
| 42H | 42J | 95K | 40HH | 44GG |
| 44H | 44J | 100K | 42HH | 46GG |
If the H you're wearing came from a US-labelled brand, it is probably a 9-inch cup instead — in which case your UK equivalent is G, and our G cup guide is the more accurate reference for your volume.
H Cup Across Six Sizing Systems
The 11-inch differential stays constant; only the label and band number change. EU runs furthest ahead because it has no double letters.
| System | 32 Band | 34 Band | 36 Band | 38 Band | 40 Band | 42 Band |
|---|---|---|---|---|---|---|
| UK | 32H | 34H | 36H | 38H | 40H | 42H |
| US | 32J | 34J | 36J | 38J | 40J | 42J |
| EU / DE | 70K | 75K | 80K | 85K | 90K | 95K |
| French / Spanish | 85K | 90K | 95K | 100K | 105K | 110K |
| Australian / NZ | 10H | 12H | 14H | 16H | 18H | 20H |
| Japanese | 70K | 75K | 80K | 85K | 90K | 95K |
For every cup letter across all systems, see our international bra size conversion chart.
Verify You're an H Cup — Free Multi-Country Calculator
Two measurements, one subtraction, and you'll know — in every sizing system at once. Because H is where the systems diverge hardest, seeing them side by side is the entire point.
Find Your Size Across Six Countries
Enter your underbust and full bust below. Results show UK, US, EU, French, Australian and Japanese equivalents plus your sister sizes — so you can shop across brands without tracking conversions manually.
H Cup Sister Sizes — 32HH and 36GG
Bras come in fixed sizes; bodies don't. Sister sizing gives you equivalent options holding the same cup volume on a different band — down one band and up one cup, or up one band and down one cup. For a UK 34H, that's 32HH and 36GG.
Band First, Always
Cup fits but the band rides up? Sister-down to 32HH. At H cup a loose band degrades support faster than at any smaller size, because the band is carrying over two pounds per side and a slack one hands that load straight to your shoulders.
Band feels tight, or your size is out of stock? Sister-up to 36GG — same cup volume, roomier band. For the full framework, see our sister sizes guide.
Is an H Cup Bigger Than DDD? Is DDD the Same as H?
Two of the most-asked H cup questions, and the answer to both is the same fact: no, DDD and H are not the same size, and H is larger — by two to five cup sizes depending on which system the H comes from.
DDD is a 6-inch bust-to-underbust difference. It is the US label for what UK sizing calls E, and it sits one step above DD. An H is either 8 to 9 inches (US convention) or 11 inches (UK convention). So:
| Size | Differential | Distance from DDD |
|---|---|---|
| DDD (UK E) | 6 inches | — |
| US H | 8–9 inches | Two to three cups larger |
| UK H | 11 inches | Five cups larger |
The confusion comes from US ladders that run DD → DDD → DDDD → G → H, which makes H look only a couple of steps above DDD on the label even though the volume gap is substantial. If you are currently in DDD and it spills, H is unlikely to be your next step — DDDD, G or the UK equivalents sit between them. Our DD cup guide and G cup guide cover the sizes in between.
H Cup vs HH Cup
HH is one cup larger than H in UK sizing — a 12-inch bust-to-underbust differential against H's 11. The ladder continues G, GG, H, HH, J. In US labelling, HH usually appears as K.
If your H cup bras spill consistently at the top or sides after a proper swoop-and-scoop, HH is the likely answer rather than a bigger band. Re-measure to confirm whether your differential is 11 or 12 inches before sizing up — at this end of the range a single inch is a full cup, and guessing is expensive.
Put the bra on, lean forward, and sweep each breast from the side and underneath fully into the cup before standing upright. A large share of people who think they need a bigger cup are wearing an un-scooped one. If you scoop and then spill, that's a real signal to size up. If everything sits clean, the size is right.
H Cup Volume Across the Band Range
The cup letter is constant; the volume is not. At H cup each band step adds roughly 15% more capacity, and because the base is already large the absolute differences are substantial. A 44H holds well over twice the tissue of a 30H.
What Do H Cup Breasts Look Like?
There is no single answer, and the reason is structural. A cup letter describes a ratio, not an absolute volume — so an H on a 30 band and an H on a 44 band are proportionally comparable but hold very different amounts of tissue, as the spectrum above shows. Add the US/UK divergence and "H cup" can describe volumes two full cups apart.
Breast shape varies independently of size too. Round, teardrop, projected, shallow, wide-set and close-set shapes all occur at H, and shape drives both appearance and which bras fit far more than the letter does. Two people who both wear 34H can look markedly different and both be correctly sized. Our breast shapes guide covers each type and the cuts that suit them.
Best H Cup Bras — What Actually Holds
At H cup, construction is not a preference. The cup needs genuine architecture — wide-set wires, reinforced side panels, three-piece cups, firm bands and wider straps — to hold shape and distribute two to four pounds per side through a full day. Brands that extend a 34C pattern upward rather than designing for full-bust fit poorly here, and the difference is obvious within an hour of wear.
| Style | Works at H cup? | What to look for |
|---|---|---|
| Full coverage | Essential | The H cup workhorse — cup wraps further round, band and wires do the structural work |
| Side support | Excellent | Internal panels push tissue forward and centre; the biggest single upgrade at H |
| Balconette | Good | Only three-piece, full-bust-specific cuts — not scaled-up standard balconettes |
| Minimizer | Good | Redistributes projection for a cleaner line under shirts and tailoring |
| Plunge | Workable | Needs a reinforced centre panel and angled wires; look for "full-bust plunge" |
| T-shirt / moulded | Workable | Harder to grade well at H — check the cup is genuinely shaped, not just foamed |
| Strapless | Difficult | Only heavily boned, silicone-gripped longline styles; sister-down for band grip |
| Bralette / wireless | Rarely | Only if explicitly engineered for H+ with internal structure |
Four Things Every H Cup Bra Needs
- A band that carries 80–90% of the load — level all the way round, snug on the loosest hook, and firm enough that it doesn't move when you raise your arms.
- Wires that sit on ribcage, never on tissue — they should trace the breast root and tack flat at the centre gore.
- Three-piece or side-support cups — seamed construction shapes and holds in a way a single moulded piece can't at this volume.
- Straps at least ¾ inch wide, ideally leotard-back or convertible — they fine-tune; they should never be doing the lifting.
H Cup Sports Bras and Swimwear
Two categories where H cup gets under-served, and where the wrong choice is most noticeable.
Encapsulation, Not Compression
Compression sports bras flatten the bust against the chest — at H cup that neither controls movement nor feels tolerable. What works is encapsulation: separate structured cups for each breast, ideally combined with a compression layer for higher-impact activity. Look for adjustable straps, a hook-and-eye back closure rather than a pull-over design, and a band that stays put through movement. Browse sports bras and filter to your size.
Buy Bra-Sized, Not S/M/L
Swim fabric loses structure the moment it's wet, so a top that fits acceptably dry will often fail at H once you're in the water. The fix is bra-sized swimwear — sold in 34H, 36H, 38H rather than small/medium/large, with underwire or moulded cup architecture, a firm band and adjustable straps. Triangle styles without cup engineering don't work at this size. See bra-sized swimwear.
"At H cup the tag has stopped telling you anything reliable. The same body reads as H, G, J or DDDD depending on who printed the label, and the same letter can be two cups apart between brands. Measure once, learn your differential in inches, and shop by the number. After that the letter is just a starting point."
— HauteFlair Fit Editorial Team
Common H Cup Fit Problems and How to Fix Them
| Symptom | What It Usually Means | What to Try Next |
|---|---|---|
| Band rides up the back | Band too loose — the dominant fault at H | Sister-down (34H → 32HH), or a smaller band at the same cup |
| Straps groove the shoulders | Band too loose, so straps carry the weight | Fix the band first; wider or leotard-back straps second |
| Cup spills at top or sides | Cup too small — you may be an HH | Swoop and scoop first; if it still spills, 34H → 34HH |
| Cup gapes or wrinkles | Cup too large, or shape mismatch | Try GG, or a three-piece cup instead of moulded |
| Centre gore floats off the sternum | Cup too small, or wires too narrow for your root | Size the cup up; then try a wider-wire full-bust brand |
| Ordered "H" in a new brand, arrived two cups small | Brand uses the US 9-inch H convention | Check the chart for FF and GG; if absent, size up to their J |
| Bra stretches out within months | Band too loose from the start | Buy on the loosest hook; sister-down next time |
| Nothing in your size fits the same way twice | Brand grading varies most at full-bust sizes | Prioritise full-bust specialists; test both sisters in any new brand |
Frequently Asked Questions About H Cup Size
What is an H cup size?
Is a US H cup the same as a UK H cup?
What is an H cup equivalent to?
Is an H cup big?
What do H cup breasts look like?
What are the sister sizes of a 34H?
What is the difference between H and HH cup?
Which is bigger, H or G cup?
How do I know if I'm an H cup?
What is an H cup in EU sizing?
What is a 40H equivalent to?
What is a 44H equivalent to?
How much do H cup breasts weigh?
What bras work best for an H cup?
What sports bra works for an H cup?
Does H cup swimwear exist?
Is an H cup bigger than DDD?
Is DDD the same as H?
What is the rarest cup size?
This article is for informational and educational purposes. HauteFlair is not responsible for individual fit outcomes — bra sizing varies between brands, styles and countries, and home measurements are a starting point rather than a guarantee. For best results, refer to each brand's specific size chart and consider a professional fitting consultation. Volume and weight figures are estimates drawn from bra-engineering references. Last reviewed: July 29, 2026.
