Comment by MattPalmer1086

Probably not needed.

The computation of the code is not computationally expensive (human computation is a requirement) so no real impact on server having to perform the full computation.

I guess if implemented client side it might provide a sanity check for the user before submitting, but it's more work for the human and they are almost as likely to get the checksum calculation wrong as any other part of it.

So I would probably remove it.