Anyone know about building websites?

[RhubarbAndMustard]

I need some help and title might not be completely accurate but not sure who to ask!

Am trying to source a company that can build some (reasonably complicated) online calculators. The type where you put in your salary / pension contributions, etc and find out what your future savings will be. I've googled but cant seem to find anything. Who does this kind of thing?

I expect almost any web design firm will do this, but it's worth getting several quotes before you go ahead, as charges vary widely.

I have used JavaScript in the past to do some calculations (fees charged during the conveyancing process by a firm of solicitors) which depended on the user input.

It also had a test to be sure they had JS enabled (some browsers / users disable it as a security risk).

I assume you'd add some clauses to indicate that this was an initial calculation and E+OE, to guard your self/ firm against facing legal action if something was miscalculated (!)