Weekly size for baby, different between apps?

Danelle • Appalachian American🏔 Mom of 2 princesses 👑
I have two apps that I track this pregnancy and development on. Of course one is Glow, the other is What to Expect. So for 20 weeks, Glow says baby should be about 10inches and 10 oz. What to Expect says 6 1/2 inches and 10oz. That's a pretty big discrepency! Wonder which one is more accurate?