For AI agents: a documentation index is available at the root level at /llms.txt and /llms-full.txt. Append /llms.txt to any URL for a page-level index, or .md for the markdown version of any page.
SupportLog InSign Up
GuidesAPI Reference
GuidesAPI Reference
    • Welcome to Ziptax
      • Quickstart
      • How to create an API key
      • How to find a TIC
      • Overview
      • By Address
      • By Lat / Lng
      • By Postal Code
Logo
SupportLog InSign Up
On this page
  • Choose a lookup method
  • Decision guide
  • Authentication
  • Base URL & versions
REST API

REST API Overview

Pick the right lookup method for your use case
Was this page helpful?
Previous

By Address

Door-level sales tax rate for a street address

Next
Built with

The Ziptax REST API returns U.S. (and, on supported plans, Canadian) sales tax rates for a given location. Every lookup hits the same base endpoint (GET https://api.zip-tax.com/request/v60) and you choose the lookup method by which query parameter(s) you supply.

Choose a lookup method

By Address

Street address → a single door-level rate. Ziptax geocodes the address and applies unincorporated-area and special-district adjustments. Recommended for most integrations.

By Lat / Lng

Coordinates → a single door-level rate. Skip geocoding if you already have verified lat/lng from your own pipeline.

By Postal Code

5-digit ZIP → all rates that overlap the ZIP. Useful for lookups where you don’t have a street address, but less accurate than address or lat/lng.

Decision guide

If you have…Use
A full customer shipping addressBy Address
Just street + ZIP (no city/state)By Address
Verified geocoded coordinatesBy Lat / Lng
Only a ZIP codeBy Postal Code
A storefront with a known lat/lngBy Lat / Lng

Address and lat/lng lookups return a single door-level rate that has been adjusted for unincorporated areas and special tax jurisdictions. Postal code lookups return every rate that overlaps the ZIP, with no door-level accuracy. Use address or lat/lng for compliant tax calculations.

Authentication

Every request needs an API key. You can supply it two ways, and the header is preferred for production clients.

$curl -H "X-API-Key: YOUR_API_KEY" \
>  "https://api.zip-tax.com/request/v60?address=..."

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

Base URL & versions

1https://api.zip-tax.com/request/v60

The version segment (v60) selects the response shape and feature set. Older versions (v50, v40, and earlier) remain available for backward compatibility. See the API Reference for the full response schema of each version.