curl -X POST https://yogataraapi.prahlad.app/api/astro/dasha_applicability/ \
-H "X-API-Key: $OCCULT_API_KEY" \
-H "Content-Type: application/json" \
-d '{"keys":["applicability_check"],"date_time":"2025-03-27T09:52:50.441Z","latitude":26.9124,"longitude":75.7873,"timezone_as_float":5.5,"year_option":365.256364,"start_option":"current","direction_option":"forward"}'Vedic astrology has many planetary period systems, and most of the nakshatra-based ones beyond Vimshottari are conditional: the classical texts say to use Ashtottari only when a particular condition holds in the chart, Dwadashottari only when another does, and so on. Choosing wrongly means running the wrong timeline for someone's whole life. This endpoint applies those conditions for you. It builds the Rashi, Navamsa and Dwadasamsa charts for the birth data and tests six conditional systems — Ashtottari, Chaturaseeti Sama, Dwadashottari, Dwisaptati, Panchottari and Sataabdika — each against the chart from which it is classically judged. Send the birth moment and place along with `year_option` (the length of year in days to use), `start_option` and `direction_option`, which are the same period settings the dasha endpoints take. Use the result to decide which dasha endpoint to call next.
| Field | Type | Required | Notes |
|---|---|---|---|
| date_time | string (date-time) | required | The moment to calculate for, ISO 8601. ALWAYS include an offset or a trailing Z - a value with no zone is read as Asia/Kolkata (UTC+05:30), not UTC, and can return the previous day's result with a 200. '2026-09-01T06:00:00Z' and '2026-09-01 06:00:00' are different instants and give different answers. FORMAT constraint. DRF DateTimeField: ISO-8601 only (DRF default input formats), e.g. "2026-09-01T06:00:00+05:30", "2026-09-01T06:00:00Z" or "2026-09-01 06:00:00" (no timezone = UTC assumed). |
| direction_option | string | required | forwardbackwardCase-sensitive lowercase. Anything else returns 400 "Invalid direction: must be 'forward' or 'backward'". |
| keys | array | required | Which calculations to return, as a list of names. See the key table for this endpoint; an unrecognised name rejects the whole request. One call costs one credit however many keys you ask for, so request everything you need at once rather than making several calls. applicability_checkArray of strings; only one key exists. |
| latitude | number (double) | required | Latitude of the place, in decimal degrees. Positive is north, negative is south. Example: 26.9124 for Jaipur, 40.7128 for New York. Minutes and seconds are not accepted - convert first. min -90 · max 90 |
| longitude | number (double) | required | Longitude of the place, in decimal degrees. Positive is east, negative is west. Example: 75.7873 for Jaipur, -74.0060 for New York. Note the sign: a missing minus puts New York in China. min -180 · max 180 |
| start_option | string | required | currentnextpreviousCase-sensitive lowercase. Anything else returns 400 "Invalid start value: must be 'current', 'next', or 'previous'". Max length 100 per. |
| timezone_as_float | number (double) | required | UTC offset of the place, in hours, as a decimal. Example: 5.5 for India (UTC+05:30), -5 for New York in winter, 5.75 for Nepal. This is NOT validated against date_time - if the two disagree you get a successful response for the wrong moment, so derive both from the same source. Use the offset in force on that date, not today's: a summer birth in a country with daylight saving needs the summer offset. min -12 · max 14 |
| year_option | number (double) | required | 365.256364365.24219365.25365360min 360 · max 365.256364 |
Ask for exactly the calculations you want by listing them in keys. An unknown key rejects the whole request, and you are charged 1 credit however many you ask for — so batch them.
| Key | Extra fields needed | Description | |
|---|---|---|---|
| applicability_check | — | The conditional nakshatra dasha systems whose classical eligibility conditions this chart satisfies, as a list of display names drawn from "Ashtottari Dasha", "Chaturaseeti Sama Dasha", "Dwadashottari Dasha", "Dwisaptati Dasha", "Panchottari Dasha" and "Sataabdika Dasha". An empty list means none of the six applies. Vimshottari is unconditional and is not among them. |