> This page is for version v6.0 (default).
> For other versions, use one of these documentation indexes:
> - v6.0 (default): https://docs.zip.tax/v-6-0/llms.txt
> - v5.0: https://docs.zip.tax/v-5-0/llms.txt

> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.zip.tax/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.zip.tax/_mcp/server.

# Welcome to Ziptax

<div className="stat-strip">
  <div className="stat-tile">
    <div className="stat-num">12,000+</div>
    <div className="stat-label">U.S. tax jurisdictions</div>
  </div>
  <div className="stat-tile">
    <div className="stat-num">80,000+</div>
    <div className="stat-label">geographic boundaries</div>
  </div>
  <div className="stat-tile">
    <div className="stat-num">{"US & Canada"}</div>
    <div className="stat-label">all sales tax locations</div>
  </div>
</div>

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

<div className="path-cards">
  <a className="path-card" href="rest-api/overview">
    <div className="path-card-image">
      <img src="/_fern-files/ziptax.docs.buildwithfern.com/41d98b01c05d8f8626e325d11356df1622084391ee9c69bd1d8aa4d949bdacc8/docs/assets/path-api.svg" alt="Ziptax REST API" />
    </div>
    <div className="path-card-body">
      <h3>REST API</h3>
      <p>The foundation of the Ziptax service. Simple key based auth, predictable JSON responses, extensible response objects.</p>
    </div>
  </a>
  <a className="path-card" href="agents-and-llms/overview">
    <div className="path-card-image">
      <img src="/_fern-files/ziptax.docs.buildwithfern.com/8a91f864fdddcc31fb82960cf27e6bb13bf6fe387cf63129cff7e76d1a0090ab/docs/assets/path-agents.svg" alt="Ziptax agents and LLMs" />
    </div>
    <div className="path-card-body">
      <h3>{"Agents & LLMs"}</h3>
      <p>Plug Ziptax into Claude, Cursor, Devin, or any MCP-compatible agent. Installable Claude Skill, hosted MCP server, and a machine-readable OpenAPI spec.</p>
    </div>
  </a>
  <a className="path-card" href="sdks/overview">
    <div className="path-card-image">
      <img src="/_fern-files/ziptax.docs.buildwithfern.com/58d82e21e1d1540bbb69bbe8e873103e463d3811e69107cb37cc2e7b0f89552f/docs/assets/path-sdks.svg" alt="Ziptax SDKs" />
    </div>
    <div className="path-card-body">
      <h3>Language SDKs</h3>
      <p>Idiomatic Go, Python, and Node.js clients with typed models, built-in retries, and full support for every Ziptax API feature.</p>
    </div>
  </a>
</div>

## Why Ziptax

<Cards>
  <Card title="Nationwide Coverage" icon="fa-solid fa-map">
    Sales tax rates for every U.S. address and jurisdiction across all 50
    states, plus Canadian rates on supported plans.
  </Card>
  <Card title="Real-Time Lookups" icon="fa-solid fa-bolt">
    Fast, reliable responses on every request. No batch jobs, no
    overnight syncs.
  </Card>
  <Card title="Address or Coordinates" icon="fa-solid fa-location-dot">
    Query by free-form street address, latitude/longitude pair, or
    postal code.
  </Card>
  <Card title="Simple Auth" icon="fa-solid fa-key">
    API key via header or query parameter. No OAuth dance required.
  </Card>
  <Card title="Product Codes" icon="fa-solid fa-tag">
    Optional per-item Taxability Information Codes (TICs) for precise
    product-level tax calculations.
  </Card>
  <Card title="Developer-First" icon="fa-solid fa-code">
    OpenAPI 3 spec, predictable JSON responses, language SDKs, and an MCP
    server for AI agents.
  </Card>
</Cards>

## 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](https://platform.zip.tax).

## Quick example

```bash
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](tutorials/quickstart) gets
you from signup to your first SDK call in five minutes.

## Where to next

<Cards>
  <Card
    title="Language SDKs"
    icon="fa-solid fa-cube"
    href="sdks/overview"
  >
    Idiomatic Go, Python, and Node clients for the Ziptax API.
  </Card>
  <Card
    title="REST API Guides"
    icon="fa-solid fa-percent"
    href="rest-api/by-address"
  >
    Step-by-step walkthroughs for lookups by address, coordinates, or
    postal code.
  </Card>
  <Card
    title="Agents & LLMs"
    icon="fa-solid fa-robot"
    href="agents-and-llms/overview"
  >
    MCP server, Claude Skill, and OpenAPI resources for AI integrations.
  </Card>
  <Card
    title="API Reference"
    icon="fa-solid fa-code"
    href="/api-reference"
  >
    Explore every endpoint, parameter, and response schema.
  </Card>
</Cards>

## Pricing & support

See [zip.tax/pricing](https://zip.tax/pricing) for plan options. Need
help? Reach us at
[support@zip.tax](mailto:support@zip.tax).