# US ZIP Code Lookup

> US ZIP Code Lookup is a paid API for AI agents from geo-us.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-29).

Converts a 5-digit US ZIP code to place name, state, and centroid coordinates; optionally validates that the ZIP belongs to an expected state.

## Facts

- Endpoint: GET https://geo-us.x402tookit.com/zip-lookup?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/us-zip-code-lookup-892208bc
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_zOZ4XT3sSCcdIBu_PtwZx

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability us-zip-code-lookup-892208bc
```

Example prompt: What city and state does ZIP code 10001 belong to, and can you confirm it's in New York? Give me the centroid coordinates too.

## When to prefer this

Use this endpoint when you need to resolve a US ZIP code to a human-readable place name and state, optionally with centroid coordinates for mapping, or when you need to validate that a ZIP code belongs to a particular state. Prefer it over full address geocoding when you only have a ZIP and don't need street-level precision, and over a generic geocoder when the optional state-verification verdict is needed.

## Known failure modes

- Invalid or non-existent ZIP code returns null or empty places array
- ZIP code with fewer or more than 5 digits may fail validation
- State abbreviation typo may cause incorrect matchesExpectedState result
- Degraded flag may indicate the underlying data source was partially unavailable
- Network or payment failure (x402) may prevent the call from completing

## How this service works

US ZIP code to place name, state and centroid; optionally verify it belongs to a state you expect.

## Output

Returns the ZIP code, the place name(s) associated with it, the full state name and abbreviation, latitude and longitude of the centroid, a source URL, and (when a state was specified) a boolean matchesExpectedState field plus a verdict and reasons explaining whether the ZIP belongs to the expected state. Also includes a freshness timestamp (asOf) and optional degraded/disclaimer flags.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "zip"
     ],
     "properties": {
      "zip": {
       "type": "string",
       "description": "5-digit US ZIP code"
      },
      "state": {
       "type": "string",
       "description": "Optional state (abbreviation or name) to verify against"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "zip": {
       "type": [
        "null",
        "string"
       ]
      },
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "places": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "object",
        "properties": {
         "place": {
          "type": [
           "null",
           "string"
          ]
         },
         "state": {
          "type": [
           "null",
           "string"
          ]
         },
         "latitude": {
          "type": [
           "null",
           "number"
          ]
         },
         "longitude": {
          "type": [
           "null",
           "number"
          ]
         },
         "stateAbbr": {
          "type": [
           "null",
           "string"
          ]
         }
        }
       }
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ]
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "sourceUrl": {
       "type": [
        "null",
        "string"
       ]
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
 
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/us-zip-code-lookup-892208bc/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from geo-us.x402tookit.com](https://www.zero.xyz/host/geo-us.x402tookit.com/llms.txt)