Size 38M Bikinis
Also labeled UK 38J and EU 85M
A 38M bikini top works like a bra you can swim in, so size it by band and cup. On a larger band, ties and hooks both need to stay firm once wet. Check conversions in our Cup-Sized Bikini Size Chart before you choose.
Getting the Band Right on 38M Bikini Tops
On a 38 band, the bikini band carries most of the weight of the cups, so it needs to feel firm all the way around. If the band digs in at the sides, it may be too tight, or too narrow to spread the pressure. Turn sideways to a mirror and make sure the band sits as low at the back as at the front.
Twist side to side in the 38M top and watch the center. It should stay close to your chest, which tells you the band and cups are working together.
When 38M Bikini Cups Cut In
An M cup needs depth from the base up, so look for cups that hold you without pushing tissue toward the top edge. If you see spill at the top or sides, the cup is too shallow for you, even if the band fits well. Look for a smooth line where the cup meets your skin at the top and under your arms.
UK tags call it 38J. Because UK sizing doubles some letters, the US M lands on J.
When 38M Bikini Straps Dig In
Straps should steady the cups, not lift them. If 38M straps leave marks, loosen them and see whether the band holds the top in place. With a very full, projected cup, wider straps can feel more comfortable, but they will not fix a loose band.
See also: 38M bras.
Frequently Asked Questions About Size 38M Bikinis
Which UK label matches a US 38M bikini top?
In UK sizing 38M reads 38J, which is not a US J, and in EU sizing it is 85M. Follow the system printed on each label.
Can I use my 38M bra size for bikini tops?
Yes, your 38M bra size is the best starting point for a bikini top sized by band and cup. Cuts vary, so check that the band stays level and the cups hold a very full, projected cup in each top.
Why does my 38M bikini top ride up at the back?
Usually the band is too loose once wet, so the cups pull it forward and up. Tighten or retie the band before you shorten the straps, since tight straps on a very full, projected cup pull the back up further.
Is a hook band better than a tie back for 38M?
No, not for everyone. A hook band keeps the same setting every time, while ties let you choose the exact length. With a very full, projected cup, pick whichever you can keep firm and level once wet.
Why does a halter top pull on my neck in 38M?
A halter puts the weight of the cups on the ties around your neck. With a very full, projected cup, that load adds up, so firm the band and consider straps that go over the shoulders.
Do 38M bikini tops and bottoms need to match in size?
No. Choose the top by your 38M bust fit and the bottoms by your waist and hip measurements. Many people wear different sizes on top and bottom.