NoExcusesGym

Yes, you can be skinny and fat at the same time. The scale will not tell you a lot. You would be surprise how many models are fat. They have a very small bone frame and little muscles. So they might look skinny even if they have a high percentage of body fat.
The best way to know of you are fat or skinny is to check your Body Composition. It is usually measured as a percentage. The best machines check percentage of lean body mass, fat, level of hydratation etc. The simple one will tell you percentage of body fat. You can ask your physician or your personal trainer to measure your level.
I like to combine at least two methods of body fat measurement. I use small electric machine and “Pinch Test”. I use a caliper for a skin fold measurement. They’ll measure 5 different points on your body in most fitness centers. I like to measure your body fat on 10 different points. I think that it is more accurate.
The most accurate way to calculate your body fat is Hydrostatic Weighing (under the water). It is also the most expensive way to find out what is your percentage of fat.
How does hydrostatic weighing calculate body fat? By using Archimedes Principle. Your examiner first calculates your body density by measuring the amount of water you displace when you immerse yourself in water. Then a formula is used to calculate body fat based on your body density. The problem is finding a facility (University, major gym or fitness center), which has a hydrostatic weighing tank!!
Focus on your overall health and step away from the scale!

(by Marcela Vanharova)