Calculators provide users with all the necessary information they seek in order to complete a purchase or at least make up their mind on which solution/service/product is right for them. By providing this info instantly and for free, you bring users closer to conversion.
When using calculators you add a smart and effective lead generation tool to your site. Prospects are very eager to share their contact details, as in return they will receive information with great value for them.
Most of the time, your site visitors are trying to solve a very specific problem - pain point. Calculators can offer actual help to the visitors by providing specific answers to that problem either by calculating a custom price or by offering personalized information.
With calculators you are in the position to collect valuable detailed information about prospects and customers regarding their preferences. This way you gain a deeper understanding of them and with this valuable input you can adjust your product offering and pricing.