---
title: "Four Transformations (四化)"
method: POST
path: "/ziwei/four-transformations"
tags: ["Zi Wei Dou Shu (Purple Star): MVP"]
---

# Four Transformations (四化)

`POST /ziwei/four-transformations`

The four stars activated by the birth year stem: 化禄 fortune, 化权 authority, 化科 repute, 化忌 obstruction. The one part of Zi Wei computable without star placement. Seven stems are agreed across traditions; for the three that are not (戊 庚 壬) every school reading ships in schoolVariants, and `school` switches the headline answer.

## Request body

- ZiweiSihuaInput
  - `date` string, required
  - `time` string
  - `timezoneOffset` number
  - `school` 'zhongzhou' | 'quanji' | 'quanshu' | 'beipai'

## Response `200`

Successful calculation

- object
  - `ok` boolean
  - `data` object
    - `solarYear` number, nullable
    - `yearStem` object, nullable
      - `pinyin` string, nullable
      - `chinese` string, nullable
    - `school` object, nullable
      - `key` string, nullable
      - `chinese` string, nullable
    - `disputed` boolean, nullable
    - `transformations` object[], nullable
      - `kind` string, nullable
      - `chinese` string, nullable
      - `name` string, nullable
      - `star` object, nullable
        - `chinese` string, nullable
        - `name` string, nullable
    - `schoolVariants` object, nullable
      - `zhongzhou` object, nullable
      - `quanji` object, nullable

## Other responses

- `400` — Validation error
- `401` — Missing or invalid API key

---

[API](https://skmtc.net/astroway/apis/astroway-calculation-api.md) · [All operations](https://skmtc.net/astroway/apis/astroway-calculation-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/astroway/astroway-calculation-api/revisions/6828e5609564/schema)