What size is medium?
1058771
The best way to find your size is: get a piece of string that can span around the perimeter of your head. then, measure that length with a regular measuring tape. Amazon provides the different measures for the different sizes of helmets. I hope this helps.
141212
The medium size is 17.7 in W X 12.6 in H X 5.9 in D: total 1343 cu in. If you are sure the small is the correct size for you, I would stay with it and compromise on the color. I have the black and gray in small which goes well in business or casual.
220783
Sorry, I responded incorrectly to your questions. I think the medium should work.
1370373
Since they are adjustable a medium should be OK. A small will be really small.
114916
I purchased the small for my 9 year old and the medium for my 16 year old. Hope that helps.
2253168
MEDIUM. My dog is very similar size and I got the medium shipped to me a week or so again, and i've put it on him around this house, it fits fine! (link to my review: www.amazon.com/review/RD3WQPAMXT5E4/ref=cm_cr_pr_perm?ie=UTF8&ASIN;=B0081XIKYG)
271279
I purchased the Large size and they fit perfect. I am a 40 waist/32 in-seam, the length is a little long but manageable. As for the medium size I am not sure.
625741
Small is 7 1/2", Medium is 8" and Large is 9". They are a perfect size as far as I am concerned.
906214
Large: 12" diameter x 8 1/2" high; medium: 8 3/4" diameter x 6 1/2" high; small: 6 3/8" diameter x 4 3/4" high.
1636660
Medium. If that doesn't work, contact their customer service dept. and they will exchange for one that will. Good luck and hope you are as happy with yours as we were!
766922
I got medium and it's too small for me.. And I'm usually wearing medium size
775893
I just guessed "Medium" and got lucky. Since I don't see any dimensions I don't know what other method to try. The previous answer is better than mine.
507964
A medium. You want it to be snug but not impossible to get in and out of. It works very well. I lost 3 pounds in 45 minutes the first time I used it.
2011182
Sorry for not responding sooner. I think with the medium size you will be fine. However, the sellers usually provide an option for exchange if their product is not fitting you.
2021364
Medium should work for you that's what have and I was about ur size when I ordered mine
1474930
I've bought a small for an adult. So I think a medium will definetely be to large, unless he is a big boy.
19228
you can look up Giro's size chart http://www.giro.com/giro/fitguide/helmet/giro_sizing_chart.pdf (medium)