---
title: "Natal chart (public, no key)"
method: POST
path: "/public/chart"
tags: ["Public"]
---

# Natal chart (public, no key)

`POST /public/chart`

Full natal chart: planets, houses, aspects, angles. Same input and same engine as the authed POST /chart, served anonymously under the public rate limit. Responses carry the free-tier `_footer` watermark. Field names are strict: `latitude`, `longitude`, `timezoneOffset`, not `lat` / `lng` / `tz`.

## Request body

- ChartInput — Birth data for a single natal chart. Required: date (YYYY-MM-DD), time (HH:mm:ss). Coordinates are latitude and longitude in decimal degrees, plus timezoneOffset in hours from UTC; the short forms lat, lon, lng and tz are rejected with 400 INVALID_FIELD. Omitting the coordinates is not the same as skipping them: houses, angles and everything derived from them are then computed for 0°N 0°E at UTC, which is a wrong answer rather than a neutral default.
  - `date` string, required
  - `time` string, required
  - `timezoneOffset` number, nullable
  - `latitude` number, nullable
  - `longitude` number, nullable
  - `houseSystem` string
  - `name` string
  - `city` string
  - `zodiacType` 'tropical' | 'sidereal'
  - `ayanamsaId` number, nullable
  - `cosmogram` boolean

## Response `200`

OK

## Other responses

- `400` — Invalid input

---

[API](https://skmtc.dev/astroway/apis/astroway-calculation-api.md) · [All operations](https://skmtc.dev/astroway/apis/astroway-calculation-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/astroway/astroway-calculation-api/revisions/793e5c2dbcdf/schema)