CharityMint is described as '501(c)(3) nonprofit that is making it easier to discover and donate to charity'. There are three alternatives to CharityMint, not only websites but also apps for Android and iPhone. The best alternative is DonorSee, which is free. Other great sites and apps similar to CharityMint are PandaPay (Paid) and Cradle giving (Freemium).
PandaPay's flexible API & simple plug-ins for processing charitable donations make it easy for any company to become a social enterprise. PandaPay saves you time and money on payment processing, compliance, disbursements and receipting.