Out of curiosity, I pulled some statistics on the US Rail network. This does cross into a bit of Canada and Mexico where the GeoFabrik extract approximated the boundary.

level_crossing	TOTAL	232167
crossing	TOTAL	8231

Rail_Bridge	47232
Rail_Tunnel	16394
Highway_Bridge	70811
Highway_Tunnel	8972

Total Layer Crossings 143409

A bridge or tunnel is counted as a single occurrence no matter how many rail lines are included. Each marked crossing node is counted, so a fully mapped rail yard could contain many crossing nodes.

For a closer look here is a breakdown of the top 20 categories of level_crossing - the first column is the type of ‘highway’, and the second column is the type of ‘railway’ in OSM:

residential	rail	112659
service	rail	29171
tertiary	rail	26789
secondary	rail	16717
unclassified	rail	12732
track	rail	10058
primary	rail	6734
residential	disused	1628
residential	light_rail	1547
residential	tram	1413
trunk	rail	1122
tertiary	light_rail	1114
secondary	light_rail	1059
service	light_rail	676
residential	abandoned	660
primary	light_rail	517
tertiary	tram	493
service	disused	435
tertiary	disused	372
residential	Unknown	371
residential	preserved	353

A type of ‘Unknown’ usually means that a node that joins ‘highway’ to ‘highway’ is marked as type level_crossing for example.

Similarly, here are the top 10 ‘crossing’ types:

footway	rail	2984
footway	light_rail	2083
path	rail	881
cycleway	rail	762
footway	tram	565
path	light_rail	116
cycleway	light_rail	96
footway	miniature	86
footway	preserved	62
residential	rail	56
service	rail	34

Note the presence of ‘residential’ and ‘service’ which are either newly incorrectly marked ‘crossing’s or a rail crossing at the junction of ‘residential’ and ‘path’ for example.

To see the complete breakdown to perform custom category groupings, obtain the raw .CSV files from Rail Crossing Counts