Begin with the birth chart
The first harmonic, H1, is the source natal chart. Every higher harmonic takes each tropical longitude measured from 0° Aries, multiplies it by an integer, and brings the result back inside a 360° circle. It is a mathematical way of folding angular separations. A planet shown at 5° Scorpio in H5 is not physically in Scorpio because of the transform; its natal position remains the original astronomical coordinate.
Our independent calculator follows that stated arithmetic and displays H2 through H10 together, plus any single whole-number harmonic from H1 to H36.
Enter a known birth time, historical UTC offset, and birthplace coordinates in the free harmonic chart calculator. Compare its natal and derived columns before assigning meaning to a close pair.
Why a conjunction appears
A natal separation of exactly 360° ÷ n becomes a full 360° turn after multiplication by n. In the derived Hn chart, the two positions meet. Other whole multiples of 360° ÷ n also meet. This is why H4 can show both a natal square and a natal opposition as conjunctions. A harmonic conjunction is a coordinate relation between two natal positions; it is not another conjunction in the physical sky.
The worked aspect examples show the calculation in degrees. The H2–H10 table identifies the principal natal divisions each chart emphasizes without assuming a fixed personality or life outcome.
Read in three passes
- Check the measured natal longitudes, birth record, and zodiac convention.
- Find close pairs in one harmonic, note its stated orb, and translate the pair back to its original angular separation.
- Place that geometric pattern beside the full natal chart and the interpretive tradition you are studying.
The calculator's conjunction list uses a 3° orb in the derived chart. In H9, a 3° derived separation corresponds to about one third of a degree from a ninth-division aspect in the natal chart. A narrow calculated match does not establish the importance of that symbolism. Different practitioners choose different harmonic numbers and orbs.
What birth time changes
A recorded time and place permit a natal Ascendant and Midheaven, which the tool can transform. The Moon can move substantially within a day, and angular points move faster still. Multiplication amplifies any uncertain longitude. With birth time unknown, the calculator uses a plainly labeled noon local-time sample and omits the Moon and angles. It assigns no houses to a harmonic wheel. See how to read a harmonic chart for a step-by-step example and the limits of an unknown-time record.