46DD Bra Size
Everything you need to know about bra size 46DD — measurements, sister sizes, international equivalents, and fit advice.
Last reviewed on 28 April 2026.
Measurements for 46DD
46DD is built for an underbust ribcage measurement that falls in the 45–47 inch range, with a full-bust measurement around 52 inches. The band number — 46 — is a fuller band size where most of the support comes from a strong, snug band rather than the straps. The cup letter — DD — describes the difference between the two measurements; a DD cup means the full bust is about five inches larger than the underbust — band integrity becomes more important from this size up.
46DD in Other Sizing Systems
EU and FR sizing read the band in centimetres, which is why 46DD maps to 105E and 120E respectively — the same body, expressed in different units. AU sizing uses a small numeric scale (24DD for this band). UK sizing shares the band number with the US but parts ways at the cup once you go past D, so 46DD reads as 46DD on a UK label.
Sister Sizes for 46DD
These sizes have the same cup volume as 46DD. 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 46DD 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 46DD
DD cups need a band that genuinely holds — most of the support comes from the band, not the straps. If straps dig in, the band is usually the size to change first.
If your 46DD 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 46DD is close but not quite right, these neighbouring sizes are the most useful next places to look:
Not sure about your size? Measure yourself and double-check.
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