Comparing the cushion-calculation systems
Calculating your cushions means predicting where the ball will arrive, or choosing where to send it, by counting diamonds instead of going by eye. The site presents several cushion-calculation systems: System 4, the One-cushion system, the Conti system and the Diamond system, plus the scale points, which are a set shot rather than a calculation. They look alike (you count diamonds, you do a small operation) but they do not answer the same question. This page puts them side by side to help you choose the one you need, and in what order to learn them.
The question to ask first
A system answers one of two questions:
- “Where will my ball arrive?” You know where you aim, and the system gives you the arrival. This is what System 4 and the One-cushion system do.
- “Where must I send it so that it arrives there?” You choose the arrival, and the system gives you the aim. This is what the Conti system and the Diamond system do.
At a glance
| System 4 | One cushion | Conti | Diamond | |
|---|---|---|---|---|
| Question | Where does my ball arrive? | Where does my ball arrive? | Where to send it? | Where to send it? |
| Shot concerned | One cushion, natural shot, after ball 2. | Crossing the width, grazing ball 2 at half-ball. | Three cushions: long, short, long cushion. | Three cushions, as a backup to the Conti. |
| Formula | gap + carry-over = 4 | CD = 4 − AB | start − arrival = aim | aim = arrival − start |
| What you read | The gap between two cushions, in diamonds. | The distance AB from the starting cushion to ball 2. | A start and an arrival on four number scales. | A start between the 2nd and the 7th diamond of the long cushion. |
| Spin | No spin. | No spin; each dose adds one diamond. | High hit with the maximum of “good” side spin. | Ball hit at the center, 2 tips of good side spin. |
| Setting at your table | A regular table is enough. | Check your positions at your table. | Four test shots to measure your table. | Theoretical values, to be checked. |
| On the site | Calculator, 6 examples, A4 sheet | Calculator, 3 positions, A4 sheet | Calculator, exercises, A4 sheet, test sheet | Calculator, 5 examples, A4 sheet |
The scale points stand apart: they are not a cushion calculation but a shot set three ways (closed, medium, open angle) to bring the balls back into a corner zone.
Which one to choose?
| Your situation | The system | Why |
|---|---|---|
| You are starting out with diamonds | System 4 | A simple rule (gap + carry-over = 4), one cushion, no spin: the best way in. |
| The shot crosses the width of the table, grazing ball 2 | One-cushion system | A single line, CD = 4 − AB, to work out where the ball arrives on the opposite cushion. |
| You want to score on three cushions and you choose your arrival | Conti system | You fix the arrival, a subtraction gives you the aim. To be tuned to your table with the test shots. |
| The Conti does not work, a ball is on the line of aim | Diamond system | Same principles, other reference marks: useful as a backup for a start between the 2nd and the 7th diamond. |
| All three balls are grouped in a corner and you want to keep them there | Scale points | A shot to set according to the angle, not a cushion calculation. |
In what order to learn them?
- System 4, to learn to read diamonds and predict an arrival.
- The One-cushion system, which reuses the same reflexes across the width of the table.
- The Conti, when you are comfortable with diamonds and want to play three-cushion. Go through Test your table first to set the system to your table.
- The Diamond, as a complement to the Conti, for the cases where it does not work.
What they have in common
- They are counted in diamonds, the reference marks on the cushions.
- They only hold if the shot is repeated identically: same hit, same speed, same ball fullness.
- These are theoretical values: your table, its cloth and its cushions shift them. Check them at your table before relying on them.
Key points
- Two families: those that give the arrival (System 4, One-cushion system) and those that give the aim (Conti, Diamond).
- To start, System 4; to play three-cushion, the Conti, with the Diamond as a backup.
- Scale points are a set shot, not a cushion calculation.
- Whatever the system: the same cue stroke every time, and a check at your table.
⎙ Printable A4 sheet The four systems side by side on one page.
⚠️ This comparison summarizes the page of each system: for the detail and the calculators, go to the page of the system concerned.