According to recent studies, BMI (body mass index) is the most common and most used method to determine ideal body weight. According to health experts, this method more accurately shows weight by reference to length. What you need to keep in mind is that this method is not 100% accurate as you must also refer to the muscular, fat, bone, or amount of fluid you have in the body.
However, we have a general idea of it. To read this, keep in mind that weight is first for women and second for men, in three divisions: Weak, Medium, Fat.
Thus, for a person 170 cm, a female 56 kg is called weak, while for a male it is 62 kg. The average weight for the female 170 cm is 60 kg, while for the male is 67 kg, while the female is called 65 kg for 170 cm and 74 kg for the male 170 cm.
Here is a table showing the "ideal" weight referring to the length: