Is there a way to get size of something?
Register, number, variable...

sizeof al = 1
sizeof eax = 4
sizeof var = 8 ; var rq 1
sizeof 1 = 1
sizeof 300 = 2
sizeof 0x123456 = 4
sizeof qword [ecx] = 8

fasmg does have a "sizeof" operator (but the value needs to be set up appropriately when the symbol is defined), but fasm 1 has nothing like that, except for the "sizeof.FIELD" values defined by the "struct" macro that comes with standard Windows headers.