Lewis Structure Calculator

Enter a central atom, the atoms bonded to it and the overall charge, and this works the electron bookkeeping through step by step: total valence electrons, one bond to each terminal atom, lone pairs to fill the terminals, whatever is left on the centre, and multiple bonds where the centre is still short of an octet. It returns the bond orders, the lone pairs, the formal charges, the octet check, the electron domains, the VSEPR shape and the hybridisation, and draws the structure. Sulfate and nitrate are drawn differently in different textbooks, so you pick the convention and it tells you what the other one gives. It handles one central atom only, declines odd electron radicals, and does not do transition metals.