# US Census Population & Income Lookup

> US Census Population & Income Lookup is a paid API for AI agents from x402-data-bazaar.vercel.app, paid per call via x402, $0.008/call, status down (last checked 2026-10-11).

Returns US Census ACS 5-year estimates for population, median household income, and median age by ZIP code or state FIPS code

## Facts

- Endpoint: GET https://x402-data-bazaar.vercel.app/api/census/population?utm_source=zero.xyz
- Price: $0.008/call
- Payment: x402
- Status: down
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-data-bazaar-vercel-app-3ed094a0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VttsvixLDqGx8KjNXKNo8

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 x402-data-bazaar-vercel-app-3ed094a0
```

Example prompt: Pull the ACS 5-year census estimates for ZIP code 94103 — I need the population, median household income, and median age.

## When to prefer this

Choose this endpoint when you need authoritative US Census demographic data (population, income, age) at the ZIP code or state level using ACS 5-year estimates. Prefer this over general web search when you need structured, numeric demographic data directly from the Census Bureau without scraping. Best for enriching address data, building demographic profiles, or performing income/population analysis at granular geographic levels.

## Known failure modes

- Invalid or non-existent ZIP code returns empty data array or error
- Invalid state FIPS code (e.g. non-two-digit or out-of-range) returns error or empty result
- Omitting both zip and state returns data for all states which may be large
- Census API upstream downtime causes 502 or timeout
- Payment failure (insufficient USDC) returns 402 Payment Required before data is served

## How this service works

US Census population, median household income, and median age. Query by ZIP (?zip=20002), state FIPS (?state=06), or omit for all states. ACS 5-year estimates.

## Output

Returns a JSON object with success flag, source attribution (US Census Bureau API), survey name (ACS 5-Year Estimates 2022), and an array of location objects each containing the location name, total population, median household income in dollars, and median age in years.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "zip": {
   "type": "string",
   "description": "ZIP Code Tabulation Area"
  },
  "state": {
   "type": "string",
   "description": "Two-digit US state FIPS code"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "data": {
  "count": 1,
  "survey": "ACS 5-Year Estimates (2022)",
  "locations": [
   {
    "name": "California",
    "medianAge": 37.3,
    "population": 39356104,
    "medianHouseholdIncome": 91905
   }
  ]
 },
 "source": "US Census Bureau API",
 "success": true
}
```

## More

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