baby bottle measurement? so confused

Question

Have I gone crazy or are the bottle measurements different from bottle to bottle?? I pump using the lanisoh bottle but she drinks from tommee tippee, latch or playtex ventaire and NONE of the ounces match up! How do I know which one is accurate?  I'm freezing milk in Lansinoh bags writing 3 oz but when I pour it in the tommee tippee it says 4oz.. Is it me or what?

Answer

Yes I've definitely noticed it between bags to bottles. I don't write what the bag says, I write what was in the bottle before pouring. But I don't see a difference between my Medela bottles and my Avent bottles.

Answer

I'm having this same problem. I switched storage bags because I thought I was tripping but ran into the same problem.

Answer

Bags are not accurate!!! Pump into bottles & pour into bags. Ounces on bottle is the correct one.

Answer

I notice that from the bags to the bottle are different.