Hey, you can try to contact ZONTO company, they have written on their website that they are looking for partners to develop their ecosystem by integrating dofferent services inside their system. They have a social networking services for cryptocummunity, I think they might be interested in adding your calculator to their project through API
It is necessary to present information for the company in a special way in order to interest them. Especially it is necessary to find a person who will present this information, because the simple direction of an e-mail or a bell does not solve anything.