---
title: "Coordinates to the nearest address, plus US county, tract and block FIPS (pay per call in USDC via x402, no key)"
method: POST
path: "/x402/api/reverse"
tags: ["Afterwren"]
---

# Coordinates to the nearest address, plus US county, tract and block FIPS (pay per call in USDC via x402, no key)

`POST /x402/api/reverse`

## Request

- Base URL: `https://afterwren.cybermaxtools.com`
- URL: `https://afterwren.cybermaxtools.com/x402/api/reverse`
- Auth: none required

result: the nearest OpenStreetMap address (city, state, postal, country); census (US points): state, county and FIPS codes for state, county, tract and block.

Pay per call with x402: $0.002 per call in USDC on Base. No key, no account: an unpaid call returns 402 with the payment requirements; retry with the X-PAYMENT (x402 v1) or PAYMENT-SIGNATURE (v2) header.

## Request body

- object
  - `lat` number, required
  - `lng` number, required

## Response `200`

Results (same field names as the bulk version's dataset records) plus the free-tier limits.

- object

## Other responses

- `400`: Invalid input
- `401`: Invalid or revoked API key
- `402`: Payment Required: x402 payment requirements (body: x402Version 1 accepts[]; header PAYMENT-REQUIRED: x402 v2).
- `504`: Took too long; ask for fewer items

---

[API](https://skmtc.dev/cybermaxtools/apis/afterwren-api.md) · [All operations](https://skmtc.dev/cybermaxtools/apis/afterwren-api/llms.txt) · [OpenAPI document](https://skmtc.dev/cybermaxtools/apis/afterwren-api/revisions/1b59acb5f5b2?raw)