Olympic EZ bar=10 KILOGRAMS, which is 22 pounds.
Unless you use the same exact bar all the time,you almost have to weigh the bar before every workout. (If you are that particular).
At my gym, we have three E-Z Olympic plate bars. One weighs about 17lbs, one is about 18.5, and the other is 20lbs. I just use 20lbs as a standard. It makes counting easier. Plus, if you use collars, that puts you close to 20lbs anyway. Probably doesn’t matter too much as long as you are improving in the gym.