Professional-Precision Natal Chart Calculation
The independent Numji Astrology Engine, which forms the calculation infrastructure of the Numji Astrology Module, was compared against international astronomical references across 500 test charts generated from various dates, times, and geographical locations. All 18,889 results within the test scope passed the established professional acceptance threshold.
Planetary degrees, fundamental axes, house cusps, and sensitive points form the technical basis of natal chart interpretation. Numji helps astrologers perform their interpretations on a map calculated with high precision.
Validated calculations
The primary result groups forming the astronomical and geometric foundation of the natal chart.
PLANETARY POSITIONS
The tropical ecliptic longitudes of the Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto were validated comparatively.
FUNDAMENTAL AXES
The ASC–DSC and MC–IC axes were tested taking into account birth time, historical time zone, and geographical coordinates.
HOUSE CUSPS
The alignment of the twelve house cusps with local horizon and meridian geometry was checked on charts generated from various latitudes and longitudes.
SENSITIVE POINTS
Vertex, Lilith, and True Lunar Node calculations were included in the test scope and validated within the professional acceptance threshold.
Highlighted precision results
Summary values of absolute angular differences compared to the Swiss Ephemeris reference.
| Calculation | Average Difference | Maximum Difference | Result |
|---|---|---|---|
| Saturn | 0.00005° | 0.00014° | Passed |
| Jupiter | 0.00009° | 0.00021° | Passed |
| Uranus | 0.00009° | 0.00036° | Passed |
| Vertex | 0.00010° | 0.00135° | Passed |
| Pluto | 0.00014° | 0.00059° | Passed |
| Neptune | 0.00025° | 0.00121° | Passed |
| Mars | 0.00034° | 0.00062° | Passed |
| Sun | 0.00056° | 0.00095° | Passed |
| Mercury | 0.00073° | 0.00140° | Passed |
| True North Lunar Node | 0.00221° | 0.00711° | Passed |
Test methodology
The goal was to ensure the results rely on a wide variety of times and locations rather than a single example.
SCOPE
- Date range: 1900–2100
- 500 distinct natal charts
- A wide range of times and geographic locations
- Total of 18,889 comparisons
REFERENCE AND THRESHOLD
- Swiss Ephemeris comparisons
- NASA/JPL validations for planets
- Professional acceptance threshold: 0.01°
- Results exceeding threshold: 0
INDEPENDENT ENGINE
Swiss Ephemeris and NASA/JPL were used as comparison references. Numji's production calculations are performed by its own astrology engine without runtime dependencies on these systems.
REGRESSION CONTROL
After each development cycle, results for planets, axes, houses, Lilith, Vertex, Lunar Node, and historical time zones were re-compared to verify that previous gains were maintained.
What does this result mean for the astrologer?
Numji's natal chart feature produces more than just a visual chart; it delivers the planetary degrees, houses, axes, and sensitive points upon which interpretation relies through a verified calculation infrastructure. This allows astrologers to focus on the holistic interpretation of the chart rather than technical computations.