Definitely runs small!
938042
This is my first workout bikini/competitive swimsuit - I usually purchase "fun" swimsuits that are not meant to be extremely tight. Since I'm adding swimming to my rotation of workouts, I thought I should have a bikini that doesn't get in the way, stays on securely, and isn't frumpy.

In normal, non-competitive swimsuits, I usually take a small or extra small (especially in stores like Old Navy that have vanity sizing). My clothing size is anywhere from a 2-4 at Banana Republic, to an 8 at H&M (Euro sizes, so no vanity sizing). So I'd say I average a size 4-6. I usually can wear size small shirts. I usually find that bikini bottoms run large on me, and I often don't completely fill them out. My measurements are approximately 34/28/38.5, and I'm a 34C. According to TYR's sizing, I'm supposed to be a medium. After reading others' suggestions, I ordered a large, and it fit perfectly both on top AND bottom. I think this could still fit a woman with a small D cup, as I still had a bit of room in the top.

The "drawstring" is not really a drawstring - it is a string that can be tied in a bow or knot. It is on the interior of the waist of the swimsuit, which is why it is not shown. We'll see if it becomes bothersome.

The bottoms are still what I'd consider low-rise. They're not as low-rise as I'm used to, but this is a workout bikini, so it's not meant to be super stylish. The top does scoop down fairly low.

I'd advise looking at the TYR size chart (not whatever swim sizing you think you are in other brands), and then going 1 size up.
2421958
Good quality, but definitely fits smaller. I had to order the next size up. But, good quality.
2924280
This product runs very small! I'm normally a size 4 and I bought the 8 and it's still too small!
4380546
Definitely run small in size so I will be returning them for at least one size larger, maybe two to allow for shrinking.
619246
Beautiful colors , but runs way small ! I normally wear a 16 and ordered a 20 since other reviews said it ran small. Still too small. Disappointed they size more correctly.
1918302
These are so cute, but as others have said, definitely small. I have a 3.5 year old who has a big belly but still wears size 3 clothes. The 4 was way to small, the 5 fit but she complained it was too tight, so we went with the 6. Definitely order a size or 2 up!
4366770
Listen to the reviews, this shirt runs very small!
4961424
Cute sandals but they definitely run small.  I'd order at least one half size up!
3889749
Will have to return- These are super cute, and my daughter wanted to put them on immediately when they arrived, but they definitely run small. I would recommend ordering a size up!
1719142
Bought these for my sister in size 11; who normally wears a 10.5.  She can't even get them on!  I wear a 10 and they barely fit me.  Definitely order at least one size larger.
445460
I ordered this in a US18-20, more like US10-12!  I understand that not all sizing is the same, but I ordered over what I would normally wear as I usually prefer my jackets, overshirt's, etc to be a bit loose.  And it is entirely too small!  So instead of just ordering one size up, I recommend to anyone else order at least 3x the size you need.
3141484
This shirt definitely runs small! I am 5'1" and usually wear an XS shirt. I'm so glad I read the previous reviews about the shirt running small. I ordered a Medium and it fit perfectly over a long sleeve T (I wore it as part of a halloween costume).
2339110
Beautiful shoe but it runs small.  I am a definite size 10 but the 10 was so small I couldn't even put it on!  Sadly, I have to return them.
757834
This shirt is super cute but it does run very small. I wear a large regularly, but I wanted a somewhat baggy fit on this shirt so I ordered it in XL, the shirt I received was clearly marked XXL but the actual size was quite a bit smaller. The fit was tighter than I wanted. It still looks fine, but it's just a lot smaller than I was expecting.
4139888
Absolutely adorable but runs TINY! I ordered a Medium for my 20 lb French Bulldog and it would barely go around her body. Reordering in a L. Definitely order a size up!
2041652
These run RIDICULOUSLY small!!!!  I wouldn't even recommend wasting your time and money trying to estimate which size you need to order to accommodate your size.  I read some other reviews, gathering that it would be wise to order a few sizes bigger....I am 5'6" 150lbs, and typically wear a women's size Medium to Large shirt...I needed this for a special occasion and knew I wouldn't have time for a return/exchange, so I couldn't risk it being too small, so generously and confidently I ordered XXX-L, expecting it to fit very loosely.  WRONG!  IT WAS WAY TOO TIGHT AND IT GAPPED AT THE BUTTONS. I was soon disappointed!! If these Asian sellers are going to try to cater to the American women's sizing system in the clothing industry, then there needs to be a much better understanding of the difference between their idea of a XXX-L and ours.  NOT EVEN CLOSE!
12145
Comfy & pretty but definitely runs small! I ordered a size larger based on reviews but its still a bit tight. Love the pink color!