CalcAPI Developer Guide

Welcome to the CalcAPI Developer Guide

Your complete resource for multi-industry tax calculation integration

The CalcAPI provides real-time tax calculation for transactions across multiple industries — including retail, telecommunications, and e-commerce. Use this guide to integrate tax calculation into your applications quickly and accurately.

Quick Start Guide

Get your first tax calculation running in minutes. Covers authentication, basic requests, and response handling.

API Reference

Full endpoint documentation with request/response schemas, field definitions, enumerations, and code samples.

Common Use Cases

Real-world scenarios including multi-item invoices, tax-exempt transactions, quote-to-order workflows, and retroactive adjustments.

Get Started with the Quick Start Guide