What are the seven chart shapes?

Bowl, bucket, locomotive, bundle, seesaw, splash and splay, as described by astrologer Marc Edmund Jones. Each describes how your planets are spread around the wheel.

What if my chart fits two shapes?

It happens often. The calculator reports the closest shape and notes when a second one is also near, so you can read both.

Does my birth time change my chart shape?

Very rarely. Planet positions barely depend on birth time, so the shape is usually the same. Only the Moon can change sign on a given day.

Does the calculator include aspect patterns?

It lists the main ones it finds, such as a T-square, yod, grand trine and stellium, next to the shape.

Chart shape calculator

The chart shape calculator looks at how your ten planets are spread around the zodiac wheel and names the closest of the seven classic shapes. It also lists the aspect patterns found in the chart. The calculator is not live yet, so this page explains what it measures and how to read the result.

What does the chart shape calculator measure?

It measures the gaps between planets. The shape depends on how wide the occupied part of the wheel is, how big the largest empty stretch is, and whether the planets fall into clusters. These measurements are matched against the definitions in the system of Marc Edmund Jones.

Shape	What it looks like	Core meaning
Bowl	All planets in about half the wheel	Concentrated, self-contained
Bucket	A bowl plus one planet alone in the empty half	One strong outlet
Locomotive	Planets over about two thirds, one third empty	Driven, self-reliant
Bundle	All planets within about a third	Specialist, deep focus
Seesaw	Two opposing groups	Weighs two sides
Splash	Planets spread evenly around the wheel	Versatile, wide interests
Splay	Uneven clusters with gaps	Individual, several strengths

How does the calculator decide on a shape?

It works through a series of questions. First, how wide is the span of all planets? A very tight span points to a bundle. About half the wheel points to a bowl or bucket, and about two thirds with a clear gap points to a locomotive. Second, are there two groups facing each other? That suggests a seesaw. Third, if none of these fit, is the spread even? Then it is a splash. If it is uneven with clusters, it is a splay.

Few charts match a shape perfectly, so the calculator allows some tolerance. It tells you when a chart sits close to a second shape. When that happens, read both pages, since the chart carries a blend of the two.

How do I read my result?

Start with the shape’s page. It explains what the shape means and how to spot it by eye. Then check the details the calculator highlights.

Leading or handle planet. In a locomotive or a bucket, this planet matters most.
The empty area. Note which houses and signs have no planets.
Aspect patterns. A T-square, yod, grand trine or stellium adds a second layer to the shape.

Shape is a first impression. It shows where energy gathers, though it says nothing about how well each planet works. Pair it with the planet strength calculator for that.

Is the chart shape exact?

Astrologers use slightly different cut-offs, for example for how empty a gap must be or how many signs count for a splash. We use the common definitions and show our reasoning, so you can see why a chart was placed in a shape. Treat the result as a helpful way into the chart and hold the label loosely.

What do I need to use it?

The date and place of your birth. Time rarely changes the result. For a full view, the birth chart calculator shows the shape alongside your wheel, planet strengths and core type. All shapes and patterns are collected in the patterns section.