We recommend you to combine the Weight Measurement and Eye-Chin Distance Measurement to pick the right size.
Instruction for Eye-Chin Distance Measurement:
You need a wall mirror, a ruler, and something flat (like a book).
1, Look straight ahead into the mirror, keep your head upright.
2, Place the ruler, starting from your lower eyelid, straight down and parallel to the mirror.
3, Meanwhile, with your mouth closed, hold the book parallel to the ground and let it touch your chin.
4, Now you can check the number at where the ruler crosses your book.
Eye-Chin Distance (CM)
Eye-Chin Distance (IN)
Less than 8.5
Less than 3.3
8.6 - 10.5
3.4 - 4.1
10.6 - 11.5
4.2 - 4.5
If you get different recommendations from the 2 methods, follow the one from the Eye-Chin Distance measurement.
If your weight or eye-chin distance is on the border line, pick the bigger one to ensure a better fit.