POST/v1/western/synastry/chart

Western · Synastry · Chart API

Western synastry overlay of two natal charts.

Get free API key Try in playground Full schema in docs

About the engine

Part of the Compatibility engine

All compatibility endpoints in one cluster: 8-koot Gun Milan, 10-koot Dashakoot, Tamil-tradition Nakshatra + Thirumana Porutham, Western synastry / composite, Western zodiac quick-check, and Ank Milan numerology. Plus batch scoring for matrimony portals (up to 500 pairs per call), Papa Samyam malefic-balance for couples, and an async PDF compatibility report.

Request

Try it from the command line

curl -X POST 'https://api.astronode.dev/v1/western/synastry/chart' \
  -H 'Authorization: Bearer aie_test_REPLACE_WITH_YOUR_API_KEY' \
  -H 'Accept: application/json' \
  -H 'Content-Type: application/json' \
  --data '{
  "person_a": {
    "date": "1993-07-04",
    "time": "09:27:11",
    "tz_offset_minutes": 330,
    "lat": 31.7473,
    "lng": 77.7754
  },
  "person_b": {
    "date": "1994-11-22",
    "time": "18:45:00",
    "tz_offset_minutes": 330,
    "lat": 28.6139,
    "lng": 77.209
  }
}'

Paste and run - this is the exact payload our live playground sends to this endpoint, so it is valid against the current schema. Every AstroNode endpoint needs a bearer token from your dashboard. Test keys (aie_test_*) work on the free tier - 1,000 requests / month, no card.

Request schema

Fields POST /v1/western/synastry/chart accepts

Request body fields for POST /v1/western/synastry/chart
Field	Type	Notes
`person_a`required	`object`	-
`person_a.date`required	`string`	pattern ^\d{4}-\d{2}-\d{2}$ e.g. `1993-07-04`
`person_a.time`required	`string`	pattern ^\d{2}:\d{2}(:\d{2})?$ e.g. `09:27:11`
`person_a.tz_offset_minutes`required	`integer`	Offset from UTC in minutes (e.g., 330 for IST) -840..840 e.g. `330`
`person_a.lat`required	`number`	-90..90 e.g. `31.7473`
`person_a.lng`required	`number`	-180..180 e.g. `77.7754`
`person_b`required	`object`	-
`person_b.date`required	`string`	pattern ^\d{4}-\d{2}-\d{2}$ e.g. `1993-07-04`
`person_b.time`required	`string`	pattern ^\d{2}:\d{2}(:\d{2})?$ e.g. `09:27:11`
`person_b.tz_offset_minutes`required	`integer`	Offset from UTC in minutes (e.g., 330 for IST) -840..840 e.g. `330`
`person_b.lat`required	`number`	-90..90 e.g. `31.7473`
`person_b.lng`required	`number`	-180..180 e.g. `77.7754`
`include_minor_aspects`	`boolean`	-

Generated from the same OpenAPI 3.1 document the API validates against, so this table cannot drift from the endpoint without the build failing.

Response

What you get back

Every AstroNode response uses the same envelope: request_id, data (the endpoint-specific payload), interpretation (optional narrative block), and meta (engine version + computed_at timestamp). This endpoint documents 200, 400, 401, 429.

The data payload for POST /v1/western/synastry/chart is not yet broken out field by field in the published schema. The fastest way to see its exact shape is to run the call - the playground returns a live response with no signup, and the API reference carries the full document.

Engine highlights

What the Compatibility engine ships

Ashtakoot Gun Milan with cancellation-aware koot scoring
Dashakoot (10-koot) variant for South Indian traditions
Porutham - both Nakshatra (Kerala-tradition) and Thirumana (Tamil-tradition marriage) variants
Western synastry + composite (chart + aspects for each)
Ank Milan numerology compatibility - three facets
Western sun-sign × sun-sign quick check
Batch scoring (up to 500 pairs/call) for matrimony-portal workflows
Papa Samyam couple malefic-balance + async detailed PDF report

Related endpoints