Avalara offers cloud based sales tax management services. With services such as AvaTax, users can manage their sales taxes, exemption certificates, and filing compliance.
The AvaTax API exposes the functionality of the AvaTax service. With it users can get applicable tax details for the given geographic coordinates and sale amount, calculate the tax for one or more invoiced items, validate the supplied address and more. The API uses RESTful calls and responses are formatted XML and JSON.