Cup guide

GG Cup Size (UK)

A GG cup is a UK cup letter for a bust measurement 10 inches larger than the band. It sits between G and H on the UK ladder, and it is a US J and an EU J.

What it means

What is a GG cup?

Quick answer

A GG cup in UK sizing means the fullest bust measurement is 10 inches (≈ 25 cm) larger than the underbust band. In US sizing the same 10-inch difference is labelled J; in EU sizing J. It is not a fixed volume: what the cup holds grows with the band it sits on.

GG cup on every bandTap a size

Same letter, nine volumes. A 28GG and a 44GG are both “GG cups”: the second holds several times the volume of the first.

By band

Every GG-cup size

The same 10-inch difference on each band. Read across for measurements, sister sizes and the EU / FR / AU labels; tap a size for its full guide.

Size	Underbust	Bust	Sister sizes	EU · FR · AU
28GG	27–28″ · 69–71 cm	38″ · 97 cm	— · 30G	60J · 75J · 6GG
30GG	29–30″ · 74–76 cm	40″ · 102 cm	28H · 32G	65J · 80J · 8GG
32GG	31–32″ · 79–81 cm	42″ · 107 cm	30H · 34G	70J · 85J · 10GG
34GG	33–34″ · 84–86 cm	44″ · 112 cm	32H · 36G	75J · 90J · 12GG
36GG	35–36″ · 89–91 cm	46″ · 117 cm	34H · 38G	80J · 95J · 14GG
38GG	37–38″ · 94–97 cm	48″ · 122 cm	36H · 40G	85J · 100J · 16GG
40GG	39–40″ · 99–102 cm	50″ · 127 cm	38H · 42G	90J · 105J · 18GG
42GG	41–42″ · 104–107 cm	52″ · 132 cm	40H · 44G	95J · 110J · 20GG
44GG	43–44″ · 109–112 cm	54″ · 137 cm	42H · —	100J · 115J · 22GG

At a glance

The GG cup, in numbers

Bust − band10″ · 25 cm

US letterJ

EU · FR · IT · DEJ

AU / NZ letterGG

Cup step10 of 15 (AA–K, UK)

Mainstream stockSpecialist

Volume is the pairing, not the letter. On a 34 band a GG cup holds about 1150 g per breast by the clinical estimates; on a 40 band about 2395 g. Its sisters on a 34 are 32H and 36G.

Context

Is a GG cup big?

Ten inches of difference is deep by any measure: roughly 1.15 kg per breast on a 34 band and over 2 kg on a 40 by the clinical estimates. This is the range where construction decides whether a bra works at all, and where a firm band at the measured size is not optional.

GG is the cup most often reached by women who were wearing a 36DD or 38DD from an add-four fitting: snug measurement moves them down two bands and up four or five cups, and the new letter looks implausible until the bra is on.

Key takeaway: “GG cup” describes a 10-inch difference in UK letters. Volume depends on the band; convert by position, never by letter.

Myths and fit

What people get wrong about GG cups

The myth“GG is a made-up size.”The realityGG is the tenth position on the UK ladder, one inch deeper than G, cut by every UK full-bust house. It reads oddly to US eyes because the US names the same cup J.

The myth“Nobody is a GG.”The realityGG on a 30 or 32 band is one of the sizes the add-four rule hides most reliably, mislabelling its wearers as 36DD. It is far more common than the rails suggest.

Method check

Wearing a GG cup on a band that rides up?

The old +4 rule inflates the band by four inches and understates the cup by two letters. If a chart gave you a GG cup on a loose band, the snug-measure equivalent is two bands down and two cups up: the same volume, carried by the band.

If a +4 chart said	Snug-measure size is likely	Same volume?
32GG	28HH	Yes: the band supports instead of the straps
34GG	30HH	Yes: the band supports instead of the straps
36GG	32HH	Yes: the band supports instead of the straps
38GG	34HH	Yes: the band supports instead of the straps
40GG	36HH	Yes: the band supports instead of the straps

Equivalents

GG cup in US, EU and other systems

USD

4″ difference. Matches UK and EU letters.

UKD

Identical to US. Full-bust specialists (Panache, Freya, Curvy Kate) label in UK letters.

EUD

Identical to US. FR, IT, DE and JP use EU cup letters.

Convert any exact size with the size converter.

Construction

Bra styles that fit a GG cup

At this depth the useful constructions are few and specific: three-part seamed cups with side slings, full-cup balconettes with wide wires, and firm longlines for strapless occasions.

1On a small band (28–30)

Frame like a 28 band, also look for narrower wires and shorter straps The same GG cup is deeper and narrower here.

2On an average band (32–36)

The widest choice of styles at this cup. Molded for a smooth line, seamed for shape and lift.

3On a larger band (38–44)

The GG cup is wider and shallower; prioritise a firm, wide band and a wire that fully encloses the root. Longline and three-hook styles help.

Shape matters as much as size: see the fit guide for the five breast shapes and the constructions that suit each.

Answered

GG cup: answered

How big is a GG cup?

A GG cup is a bust 10 inches (25 cm) larger than the band, the tenth UK cup letter. On a 34 band that is about 1,150 g per breast; on a 38 band about 1,750 g. Its US equivalent is J and its EU equivalent is J.

What is a GG cup in US sizes?

A US J. UK letters run G, GG, H, HH where US letters run I, J, K. Position ten is GG in the UK and J in the US. A US G is three cups smaller than a UK GG.

Is GG bigger than H?

In UK sizing, no: GG is the tenth cup and H the eleventh. Against a US H, yes: a US H is the eighth position, two cups smaller than a UK GG.

What are the sister sizes of a 32GG?

A 30H and a 34G in UK letters hold the same volume as a 32GG.

Which brands make GG cups?

Panache, Freya, Fantasie, Curvy Kate and Elomi cut GG as a core size across most bands; Parfait reaches the same volume on select styles labelled in US letters.

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