Property data basicsWhat is a parcel number (APN)?A parcel number (APN, PIN or parcel ID) is the unique ID a county assigns to each piece of land for taxes and records. What it looks like, where to find it, and why it changes.
Owner lookupHow to find the owner of a property by addressFind who owns a house or lot from its address using free county assessor and recorder records, what to do when the owner is an LLC, and how to look owners up in bulk with an API.
Assessor dataHow to get tax assessor data through an APIYour options for programmatic access to US county tax assessor data: county bulk downloads, scraping, and normalized APIs, with what each costs in time and money, and a working example.
Permit lookupHow to look up building permits for an addressFind the permit history of a house: which office issues permits for the address, how to search the online permit portal, what to do when records are not online, and how to search permits across many properties.
Zoning lookupHow to find the zoning of a propertyFind a property's zoning district on the city or county zoning map, read what the district allows in the zoning code, and check it programmatically for many parcels.
TutorialHow to add parcel boundaries to a Mapbox or MapLibre mapShow US property lines on your own web map with hosted vector tiles: get a tile URL, add a vector source and line/fill layers, filter by field, and keep your key off the client.
AI agentsHow to give Claude, ChatGPT or Cursor access to property dataConnect a property data MCP server to Claude, ChatGPT, Cursor or Claude Code so your assistant can look up parcels, owners, assessor records, permits and zoning, with examples and cost controls.

Property data guides

Query US property data from your code or your agent.