Free 90-Degree Dial
Enter your birth details to generate a 90-degree dial with cluster detection and a guided Uranian reading surface.
What is a 90-degree dial?
The 90-degree dial is a core technique in Uranian astrology, developed by Alfred Witte and the Hamburg School in the early 20th century. It compresses the full 360-degree zodiac into a 90-degree circle by folding each position modulo 90. The result is a view where conjunctions, squares, and oppositions all appear as the same pattern — factors clustered together on the dial.
This fold reveals structures that are invisible on a standard chart wheel. Two planets in an exact square appear side by side on the dial. A midpoint that falls on a cardinal axis becomes immediately visible at 0° on the dial (representing 0° Aries, Cancer, Libra, and Capricorn simultaneously). The simplicity is the point: the 90-degree dial strips away zodiac sign information and shows pure angular relationships.
Our calculator plots all natal factors on the dial, detects clusters within your chosen orb, and optionally includes the eight Trans-Neptunian Points (Cupido, Hades, Zeus, Kronos, Apollon, Admetos, Vulcanus, and Poseidon). TNP positions are computed using Keplerian orbital elements derived from James Neely's 1978 paper — the standard reference for the astrological community.
How to read a 90-degree dial
Start by looking for clusters — groups of factors packed tightly together on the dial. Each cluster represents a set of planets, points, or TNPs that share the same hard aspect relationship. The tighter the cluster (smaller orb), the more powerful the configuration.
Rotate the dial to center a cluster at the top (0°) to inspect it. This is the traditional Uranian practice: rotating the dial so that one factor sits at the pointer and reading off which other factors align with it. Our tool lets you rotate freely with the slider.
The factor table shows both the original ecliptic longitude and the folded dial position. Use the ecliptic value when you need to know the zodiac sign and degree; use the dial position to see the 90° symmetry. For deeper analysis, use the Planetary Picture Scanner to find which midpoint equations are active in your chart.
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Frequently Asked Questions
What is a 90-degree dial?
A 90-degree dial is a circular chart that compresses the full 360-degree zodiac into a 90-degree circle. Each zodiac position is folded by dividing by 90 and taking the remainder, so 0° Aries, 0° Cancer, 0° Libra, and 0° Capricorn all land at the same point. This reveals hidden symmetries — planets that form hard aspects (conjunctions, squares, and oppositions) end up close together on the dial, making midpoint structures and planetary pictures immediately visible.
What are Trans-Neptunian Points (TNPs)?
Trans-Neptunian Points are eight hypothetical factors used in Uranian astrology, originally defined by Alfred Witte and Friedrich Sieggrün in the 1920s-30s. They are Cupido, Hades, Zeus, Kronos, Apollon, Admetos, Vulcanus, and Poseidon. TNPs are not physical objects — they are calculated points on the ecliptic with defined orbital periods. They add nuance to chart interpretation and are central to the Hamburg School tradition.
How does the 90-degree fold work?
Every zodiac longitude is divided by 90, and the remainder becomes the dial position. A planet at 5° Aries (5°), 5° Cancer (95°), 5° Libra (185°), and 5° Capricorn (275°) all fold to the same 5° position on the dial. This means any planet forming a conjunction, square, or opposition to another will appear near it on the 90-degree dial, grouped into visible clusters.
What is a cluster on the dial?
A cluster is a group of factors (planets, points, or TNPs) whose folded dial positions fall within the selected orb of each other. Clusters highlight areas of concentrated energy in the chart. The tighter the cluster, the more focused and powerful the planetary picture. Clusters often represent key themes in a person's life.
What orb should I use?
A 1.5° orb is a good starting point — it catches the most meaningful configurations without too much noise. Tighter orbs (0.5–1.0°) show only the most exact planetary pictures. Wider orbs (2.0–3.0°) reveal more patterns but include weaker connections. Experiment to see which setting reveals the most coherent themes in your chart.