Quick answers to the most common questions about 3ball.app and three-cushion carom billiards.
Rules and practice
When does a three-cushion shot score?
Your cue ball must contact both other balls and complete at least three cushion contacts before reaching the second object ball, without a foul. The first object ball may be contacted before, between or after those cushion contacts. They need not be three different cushions.
How does free carom differ?
There is no minimum cushion count. Official libre also restricts repeated scoring in marked corner zones; it is not an unrestricted version of every carom game. The simulator’s Free mode is a practice mode, not a complete referee for competition rules.
What equipment dimensions should I use?
The UMB international playing surface is 2.84 × 1.42 m between cushion noses; club formats vary. Regulation balls are 61–61.5 mm and 205–220 g, with at most 2 g difference in the set. UMB lets players choose cue length, weight and diameter; there is no compulsory 140 cm/500 g cue.
Is there one diamond-system formula?
No. Each system has its own scales, stroke assumptions and route family. In the Corner-5 convention used here, departure minus first-cushion aim equals third-cushion arrival: 5 − 2 = 3. Do not mix these numbers with another system or raw physical diamond indices.
Why does a kiss occur?
Two moving balls get close enough to collide again. Crossing drawn paths alone does not establish a kiss: arrival times and ball diameter matter too. Watch both balls together; changing speed can alter their routes as well as their timing.
What is a good average?
Average is total points divided by total innings. Sample, table and format matter; a one-match value is not a universal skill grade. Combine sessions by summing points and innings, not by taking an unweighted mean of match averages.
Using 3ball
Is payment or registration required?
The current simulator is free without an account. This describes the available service, not a promise about every future feature or pricing decision.
Which browser and connection do I need?
Use a current browser with WebGL2 enabled on a compatible device. The simulator requires internet; a lost connection pauses access until it returns. Installing the web app does not make it an offline game.
Does the solver prove that a shot will score?
No. It searches simulated candidates and compares sensitivity to small input changes within the model. This is not a measured real-table success probability; cloth, cushions, spin and placement can differ. Check promising routes on your table.
Does Photo-to-Position reproduce the table exactly?
It helps identify a table and ball locations. Inspect corners, ball identities and scale, then correct the proposed positions. Perspective, glare and hidden edges can cause errors; importing a photograph is not a physical calibration.
Where are saved positions and preferences?
They are local to the browser or app, not automatically synchronised across devices. Clearing its data can remove them. A shared position link reveals the position it contains; see the Legal page for analytics and submitted-report details.
How should I report a problem?
Use Report an issue in the app menu or the contact page. Include device, version, steps, expected result and actual result. A position link or screenshot helps; do not include passwords or private account information.
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