I'm considering migrating about 100 ArcGIS Server service layers to ArcGIS Online hosted feature layers. I need to estimate the amounts of storage the feature layers will have in ArcGIS Online (to estimate the cost).
So, given that the hosted feature layer is very similar to the geodatabase format, I used ArcGIS Pro's Catalog view to see sizes of source feature classes in file-geodatabase format. That's easy.
However, when testing a sample set of the feature classes by publishing them to ArcGIS Online as feature layers, the sizes of those feature layers in ArcGIS Online are wildly different (larger) than their source feature-class counterparts; also, the percent increase isn't linear--it varies a lot by layer.
For example, a .gdb feature class that has a size of 152.422 MB generates a feature layer that has a size of 467.781 MB; that is 3.07 times bigger.
For another example, a .gdb feature class that has a size of 315.73 MB generates a feature layer that has a size of 514.141 MB; that is 1.63 times bigger.
And another example... a 21.077 MB .gdb feature class generates a 75.797 MB feature layer; that is 3.6 times bigger.
My organization needs to know about how much it will cost to store the hundred layers. How am I supposed to estimate that without actually creating the hundred layers?