Calculate Human Design Variables - The four arrows and Color, Tone, Base substructure
post_human_design_variablesRead-only
Calculate the four Human Design Variable arrows for a birth moment: Determination and Environment on the design side, Perspective and Motivation on the personality side. Each arrow returns its Color, Tone, and Base numbers from the hexagram-line substructure, the left or right direction set by the Tone, and the sourced Color and direction labels. This is the advanced Rave Variables and Primary Health System layer beneath Type, Strategy, Authority, and Profile. Color, Tone, and Base shift with tiny differences in birth time, so each arrow carries a confidence flag that turns false near a Color or Tone boundary, and a precise birth time is essential. Built for Human Design apps offering PHS, diet, environment, and Rave Psychology readings.
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| date | Yes | Birth date in YYYY-MM-DD format. The anchor for both the Personality activations at birth and the Design activations 88 degrees of solar arc earlier. | |
| lang | No | Response language (BCP 47). Supported: en, tr, de, es, hi, pt, fr, ru, zh-Hans, zh-Hant. Defaults to en. Coverage varies by domain, and a field with no translation in the requested language returns English. | en |
| time | Yes | Birth time in 24-hour HH:MM:SS format. Precision matters: the profile lines and gate boundaries shift with the exact minute of birth. | |
| compact | No | Set true for the same data in a compact shape: arrays of same-shaped objects arrive columnar as {"__cols":[names],"__rows":[[values]]}. Lossless, typically 40 to 52 percent fewer tokens. | |
| latitude | No | Birth latitude in decimal degrees. Optional and does not affect the bodygraph, which depends only on ecliptic longitudes. Defaults to 0. | |
| nodeType | No | Lunar node convention. "mean" is the smoothed average node, which always moves retrograde; "true" is the osculating node, which tracks the real perturbed node, oscillates up to about 1.5 degrees either side of the mean on a 173-day cycle, and can briefly turn direct. Neither is more correct and they almost always fall in the same sign. Applies to the North and South Node activations. True is what professional Human Design software uses (HumanDesign.ai, Total Human Design) and is the value RoxyAPI verifies against, so leave it unset for a standard chart. It matters only when a node sits on a gate boundary, where the choice moves a node gate. Because a gate can be half of a channel, that can change the completed channels and, with them, whether a center reads defined or open, plus the definition, authority, profile or type. A chart where only one center disagrees is the usual shape, since the type and profile often survive unchanged. If another calculator disagrees on any of those, it is almost certainly using the mean node: pass "mean" to match it. Defaults to "true". | true |
| timezone | Yes | IANA name (e.g. "America/New_York", "Europe/London", "UTC"), decimal hours (e.g. -5 for EST, 1 for CET), or a fixed UTC offset (e.g. "-05:00", "+01:00"). Prefer the IANA name: it is resolved to the DST-correct offset for the birth date, while a fixed offset or decimal is taken literally and will be wrong if it does not match the daylight-saving state on that date. Invalid timezones return 400 with a validation error. | |
| longitude | No | Birth longitude in decimal degrees. Optional and does not affect the bodygraph. Defaults to 0. |