is it possible to add 2 numbers that are 200 digits long each in vb?

It is not supported in any data types that are predefined in VB. The only way you could really do this is to store the numbers in string variables (variants may make it a bit easier) and write the math functions to preform the desired tasks on your strings. This can be tricky depending upon your application. borelli34

Using string functions addition is relatively easy. When I first read the posting I thought of multiplication. Since the subject is multiplication. There is(was) a BASIC program that does arbitrary precision multiplication of large multidigit numbers. An extension of the method would use arrays to store the partial products of the multiplication. Then sum them.

Here is a solution in BASIC. tested to greater than 200 digits rem long digit addition rem PowerBasic 3.1 for DOS (should run in QBASIC) x$ = "12345567778888444444444444444444444444" y$ = "44444444444444444444444444999999004444" rem find longer string and rem pad shorter with leading "0" a% = len(x$) b% = len(y$) c% = a% if b% > a% then c% = b% x$ = repeat$((b%-a%), "0") + x$ else y$ = repeat$((a%-b%), "0") + y$ end if rem display inputs print x$ print y$ rem work variables z$ = "" w% = 0 w$ = "" rem working from end for p% = c% to 1 step -1 x% = val(mid$(x$,p%,1)) y% = val(mid$(y$,p%,1)) s% = x% + y% + w% s$ = str$(s%) z$ = right$(s$,1) + z$ rem carry if (len(s$) > 2) then w$ = mid$(s$,2,1) w% = val(w$) else w% = 0 end if next p% rem last carry if (w% > 0) then z$ = w$ + z$ end if print z$ rem variables rem x$ = first number string rem y$ = second number string rem z$ = output number string rem a% = length of first number string rem b% = length of second number string rem c% = length of longest number string rem w% = carry digit number rem w$ = carry digit string rem p% = position in number string