Stripe - Online payment processing for internet businesses. Stripe is a suite of payment APIs that powers commerce for online businesses of all sizes. Use Stripe’s payment platform to accept and process payments online for easy-to-use commerce solutions.

CALCONIC_ - Build & add interactive calculators to your website! Choose from more than 50 premade calculators or build your own from scratch. No coding required. Free plan available. Zapier Integration. Publish Anywhere.

Stripe Billing - A set of tools for billing and subscriptions

ConvertCalculator - Create powerful, beautiful Calculator forms

Winngie - A New Way to Exchange Local Currency and Send Money Abroad. No Commission No Bank. 7/24 Anywhere Anytime. Match With Real People Around You and Swap Money.

uCalc - uCalc is a universal builder of forms and calculators.