According to the weight is the method we often use. There seems to be a weight scale, and the standard weight corresponds to height, overweight and thinness. I think you can compare it yourself. Generally, our figure can be judged by our weight, such as my162,98, which belongs to normal weight, and you can also calculate your body fat.
There are also some details that can be seen visually, but they are not very accurate. After all, there are too many subjective factors. Some people think that the standard of thinness is that the calf is very thin and there is no fat anywhere. Looking at you like this may make you feel fat. Even if you don't weigh much, you will still feel bad. Others look at you objectively, but you are easily disturbed by clothes. For example, girls with thick legs like to wear wide-leg pants, so they can hardly be seen.
So the most scientific thing is measurement. The first time I measured myself was when I went to the gym. Now the gym will do this. There are special instruments to measure. My measurement results show that everything else is within the normal range, that is, fat mainly accumulates in the waist and buttocks, which should be caused by sedentary.
That's about it. I suggest the third one. Sometimes, my figure has nothing to do with my weight, especially for people who exercise. My figure of nearly 100 kg is almost the same as my previous figure of 92 kg. Everyone thinks I have lost weight. But if you look at it yourself, you will have subjective emotions, and others will be blocked by some foreign objects. The most scientific thing is instrument measurement.