How many lines of code does FieldTrip consist of?

You can count that using the following commands

roboos@mac001> cat `find fieldtrip-20221223 -name \*.m` | grep -v ' *%' | grep -v '^ *$' | wc -l
493168

or excluding the external toolboxes with

roboos@mac001> cat `find fieldtrip-20221223 -name \*.m | grep -v external` | grep -v ' *%' | grep -v '^ *$' | wc -l
237209

So the answer is approximately 237209 lines of code, excluding comments and empty lines.

To provide some historical perspective here is the number of lines in older FieldTrip releases (also only counting lines of code).