Welcome to Ziptax

Ziptax provides a developer-friendly API and an online lookup tool for precise sales tax data. By using geographic inputs such as a full street address, you can instantly determine the correct sales tax rates for any place in the United States and Canada.

12,000+
U.S. tax jurisdictions
80,000+
geographic boundaries
US & Canada
all sales tax locations

Query by address or lat/lng to get door-level accurate rates adjusted for unincorporated areas, special districts, and origin-vs-destination sourcing rules. Rates are updated in real-time. No tables to maintain, no overnight syncs.

Choose your path

Ziptax REST API

REST API

The foundation of the Ziptax service. Simple key based auth, predictable JSON responses, extensible response objects.

Ziptax agents and LLMs

Agents & LLMs

Plug Ziptax into Claude, Cursor, Devin, or any MCP-compatible agent. Installable Claude Skill, hosted MCP server, and a machine-readable OpenAPI spec.

Ziptax SDKs

Language SDKs

Idiomatic Go, Python, and Node.js clients with typed models, built-in retries, and full support for every Ziptax API feature.

Why Ziptax

Nationwide Coverage

Sales tax rates for every U.S. address and jurisdiction across all 50 states, plus Canadian rates on supported plans.

Real-Time Lookups

Fast, reliable responses on every request. No batch jobs, no overnight syncs.

Address or Coordinates

Query by free-form street address, latitude/longitude pair, or postal code.

Simple Auth

API key via header or query parameter. No OAuth dance required.

Product Codes

Optional per-item Taxability Information Codes (TICs) for precise product-level tax calculations.

Developer-First

OpenAPI 3 spec, predictable JSON responses, language SDKs, and an MCP server for AI agents.

Authentication

Ziptax supports two ways to supply your API key. Pick whichever fits your client:

  • Header (recommended): send X-API-KEY: YOUR_API_KEY
  • Query parameter: pass key=YOUR_API_KEY on the request URL

Don’t have a key yet? Create a free account at platform.zip.tax.

Quick example

$curl -H "X-API-KEY: YOUR_API_KEY" \
>  "https://api.zip-tax.com/request/v60?address=200+Spectrum+Center+Dr+Irvine+CA"

Want a guided walkthrough instead? The Quickstart gets you from signup to your first SDK call in five minutes.

Where to next

Language SDKs

Idiomatic Go, Python, and Node clients for the Ziptax API.

REST API Guides

Step-by-step walkthroughs for lookups by address, coordinates, or postal code.

Agents & LLMs

MCP server, Claude Skill, and OpenAPI resources for AI integrations.

API Reference

Explore every endpoint, parameter, and response schema.

Pricing & support

See zip.tax/pricing for plan options. Need help? Reach us at support@zip.tax.