44F Bra Size
Everything you need to know about bra size 44F — measurements, sister sizes, international equivalents, and fit advice.
Last reviewed on 28 April 2026.
Measurements for 44F
44F is built for an underbust ribcage measurement that falls in the 43–45 inch range, with a full-bust measurement around 51 inches. The band number — 44 — is a fuller band size where most of the support comes from a strong, snug band rather than the straps. The cup letter — F — describes the difference between the two measurements; an F cup in UK and EU-style sizing corresponds to about six inches of difference between full bust and underbust — this is where mainstream lingerie sizing tends to thin out and specialist fuller-bust ranges take over.
44F in Other Sizing Systems
EU, FR, and JP sizing read the band in centimetres, which is why 44F maps to 100F (EU), 115F (FR), and 100F (JP) — the same body, expressed in different units. AU sizing uses a small numeric scale (22E for this band). UK sizing shares the band number with the US but parts ways at the cup once you go past D, so 44F reads as 44E on a UK label.
The label "44F" follows the UK and broadly-European convention, where the cup letters go AA, A, B, C, D, DD, E, F. The same cup volume in US sizing is usually written as DDD (or DDD/F on labels that cross-reference both systems). If a US chart returns "44DDD" for your measurements, that is the same physical cup as 44F in UK/EU notation.
Sister Sizes for 44F
These sizes have the same cup volume as 44F. Try them if the band feels too tight or too loose.
← Tighter band, bigger cup · Looser band, smaller cup →
Sister sizes are useful when the cup of your 44F fits well but the band is wrong — too loose by the end of the day, or too tight to clip up comfortably. Going one band smaller and one cup larger keeps the cup volume the same while tightening the band; going the other way loosens the band without losing cup space. Read the full sister-size matrix if you want to see how this works for every size at once.
Fit Tips for 44F
F cups in UK sizing line up with US DDD/F. Three-part cups, side support panels, and full-coverage shapes typically fit more cleanly than thin moulded cups at this size.
If your 44F bra is gapping at the top of the cup, the cup may be too large or the wrong shape — try a demi-cup or balconette before assuming the size is wrong. If the centre piece between the cups (the gore) does not lay flat against your sternum, the cup is almost certainly too small; go up one cup. If the band rides up across your back during the day, the band has stretched out or was too loose to begin with — drop one band size and add one cup to keep the same cup volume.
For more detailed troubleshooting, the Fit Test on the home page covers six common visible problems and the size or shape change that usually addresses each one. The guide to measuring mistakes covers the most common reasons a calculation comes out wrong in the first place.
Related sizes
If 44F is close but not quite right, these neighbouring sizes are the most useful next places to look:
See every size at a glance on the full bra size index, or read how to measure your bra size if you are not sure 44F is right for you.
44F — frequently asked questions
What measurements are a 44F bra?
A 44F bra fits an underbust (ribcage) measurement of roughly 43 to 45 inches (109–114 cm) and a full-bust measurement of about 51 inches (130 cm). The cup letter F reflects the difference between those two numbers.
What are the sister sizes of 44F?
The sister sizes of 44F are 42F and 46DD. They share the same cup volume as 44F but use a different band — go to 42F for a tighter band, or up for a looser one. Try a sister size when the cup of your 44F fits but the band feels too loose or too tight.
What is 44F in UK, EU, and other sizing systems?
44F (US) converts to 44E in UK sizing, 100F in EU sizing, 115F in French sizing, 22E in Australian sizing, and 100F in Japanese sizing. The body is the same; only the labelling system changes.
Is 44F a small or large bra size?
In terms of how common it is, this size pairs a fuller band with a fuller-bust cup. There is no universal "small" or "large" bra size — the same cup letter describes a different volume on every band — but within the full range BraCalc covers (bands 28–48, cups AA–H) this combination sits toward the fuller end.
Not sure about your size? Measure yourself and double-check.
Calculate My Size