POST/api/astro/day-night-length/1 credit

Day and night length

How long the day and the night are, and where their midpoints fall. Day length is sunrise to sunset, night length sunset to the next sunrise, with local midday and midnight as the halfway moments. The two lengths add to twenty-four hours. Durations come back both as the engine's HH:MM:SS form and as a number of seconds, because dividing "13:35:43" by 3600 gives NaN in JavaScript with no error anywhere — the trap these focused endpoints exist to close.

https://yogataraapi.prahlad.app/api/astro/day-night-length/

Test Request

Authentication

Send your key in the X-API-Key header. Keys are server-side credentials — never put one in browser JavaScript or a mobile app.

X-API-Key: yt_live_a1b2c3d4_…
Content-Type: application/json

Request fields

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.
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 -89.9 · max 89.9
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
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
dhuma_vyatipata_relation	string	optional	`360_minus_dhumadhuma_plus_53_20`
eccentric_anomaly	number (double)	optional
eccentricity	number (double)	optional
gulika_portion	string	optional	`saturneighth`
gulika_rises_at	string	optional	`beginningmiddleend`
kala_mrityu_rise_at	string	optional	`beginningmiddleend`
keys	array	optional	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.
mandi_portion	string	optional	`saturneighth`
mandi_rises_at	string	optional	`beginningmiddleend`
mean_anomaly	number (double)	optional
mode	string	optional
nakshatras	string	optional
samvata_type	string	optional
tolerance	number (double)	optional

Example request

curl -X POST https://yogataraapi.prahlad.app/api/astro/day-night-length/ \
  -H "X-API-Key: $OCCULT_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"date_time":"2026-06-02T06:30:00+05:30","latitude":26.9124,"longitude":75.7873,"timezone_as_float":5.5}'

Response

{
  "data": {
    "day": {
      "length": "48943.0",
      "length_seconds": 48943,
      "midday": "2026-06-02T12:24:48+05:30"
    },
    "night": {
      "length": "37448.0",
      "length_seconds": 37448,
      "midnight": "2026-06-03T00:24:53+05:30"
    }
  },
  "status": 200,
  "is_error": false,
  "message": "successful"
}

Captured from a real call using the exact request above. Results sit under data.

Errors

Metering errors return { "error": "…", "message": "<code>", "is_error": true }. Show error to people and branch on message. See the error reference.