Pool Ball and Snooker Ball Sizes: Diameter and Weight Chart
Pool (American and 9-ball): 57.15 mm (2¼ in), 156–170 g (5.5–6 oz), under the WPA equipment specifications. Heyball (Chinese 8-ball) uses the same size.
Snooker: 52.5 mm (about 21/16 in), within ±0.05 mm. The rules set no weight, only that the balls in a set should be equal and differ by no more than 3 g.
UK pool (blackball): the rules set no size; pub and league sets are usually 2 in (50.8 mm) object balls, often with a 1⅞ in (47.6 mm) cue ball. Carom: 61–61.5 mm, 205–220 g.
"Billiard balls" covers at least four different sizes, and they are not interchangeable: a snooker ball rolls into a pool pocket with room to spare, and a pool ball is too big for a snooker set. Here is every size, with the rulebook it comes from.
Ball size chart
| Game | Diameter | Weight | Source |
|---|---|---|---|
| Pool (8-ball, 9-ball, 10-ball) | 57.15 mm ± 0.127 mm (2¼ in ± 0.005 in) | 156–170 g (5.5–6 oz) | WPA Recommended Equipment Specifications |
| Heyball (Chinese 8-ball) | 57.15 mm ± 0.05 mm | 156–170 g | WPA Rules of Heyball (2025) |
| Snooker | 52.5 mm ± 0.05 mm | Not set; a set within 3 g | WPBSA Official Rules, Section 1 |
| UK pool (blackball) | Usually 2 in (50.8 mm); cue ball often 1⅞ in (47.6 mm) | Not set | Not in the rules; usual sets |
| Carom (three-cushion) | 61–61.5 mm | 205–220 g | CEB Material Norms |
Pool balls
The WPA equipment specifications set pool balls at 2¼ in (57.15 mm), within ±0.005 in, and 5½ to 6 oz (156–170 g). They must be cast phenolic resin, unpolished and unwaxed. A set is a white cue ball and fifteen numbered balls: 1–8 solid colours (1 yellow, 2 blue, 3 red, 4 purple, 5 orange, 6 green, 7 maroon, 8 black) and 9–15 the same colours as a band on white, with the 6 and 9 underscored. The same balls are used for 8-ball, 9-ball and 10-ball, on 7, 8 and 9-foot tables alike.
Bar table cue balls: coin-operated tables with a ball return have to separate the cue ball from the object balls, so they use a cue ball the mechanism can tell apart: slightly larger or heavier, or one with a magnetic core. Ball makers such as Aramith sell both kinds. If the cue ball on a bar table feels different, it probably is.
Snooker balls
WPBSA rules (Section 1, Rule 2): a set is 15 reds, the six colours and a white, each 52.5 mm in diameter, within ±0.05 mm. There is no weight in the rules, only that the balls should be of equal weight where possible, with no more than 3 g between the heaviest and the lightest in a set. Top professional sets are matched more closely than that; Aramith sells its tournament snooker set as matched to within 1 g.
A snooker ball is about 8% smaller across than a pool ball, which is one reason pots look so small on a 12-foot table. Home snooker tables smaller than full size (6 to 10 feet) are often sold with smaller ball sets, so check what the table maker recommends.
UK pool (blackball) balls
The World Eightball Pool Federation and English Pool Association rules describe the balls (seven reds, seven yellows and the black, or numbered balls) but not their size. In practice, UK pub and league tables of 6 and 7 feet use 2 in (50.8 mm) object balls, and coin-operated tables often use a slightly smaller 1⅞ in (47.6 mm) cue ball so the table can return it separately. American-size 2¼ in balls are too big for most UK tables' pockets. How the two games compare is in English pool vs American pool.
Heyball (Chinese 8-ball) balls
Heyball uses the same 57.15 mm balls as pool, with a tighter tolerance of ±0.05 mm and a weight of 156–170 g. Since August 25, 2025, WPA heyball events use the WPA's UNITY ball set. The table and pockets are what make heyball different; see Chinese 8-ball table size and pockets.
Carom balls
Three-cushion and other carom games use three larger, heavier balls: the CEB (European carom confederation) material norms give 61–61.5 mm and 205–220 g. There are no pockets, so the extra size and weight only change how the balls travel and rebound.
Which balls go with which table?
- American pool table (7, 8 or 9 ft): 2¼ in (57.15 mm).
- UK pool table (6 or 7 ft): 2 in (50.8 mm), usually with a 1⅞ in cue ball on coin-operated tables.
- Full-size snooker table (12 ft): 52.5 mm. Smaller home snooker tables: follow the maker's recommendation.
- Heyball table: 2¼ in (57.15 mm).
Ball size and pocket size go together. A 57.15 mm ball in an 85 mm heyball pocket has about 14 mm to spare either side; in a 116 mm pool corner pocket, about 29 mm. The full comparison of the tables is in billiards vs pool vs snooker.
Same balls, different margins
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Start the aiming lesson →FAQ
What size is a pool ball?
A regulation pool ball is 2¼ in (57.15 mm) in diameter, within ±0.005 in, and weighs 5.5 to 6 oz (156–170 g), under the WPA equipment specifications.
Are snooker balls smaller than pool balls?
Yes. Snooker balls are 52.5 mm across, about 8% smaller than 57.15 mm pool balls.
What size are English pool balls?
The blackball rules do not set a size. UK pub and league sets are usually 2 in (50.8 mm) object balls, often with a 1⅞ in (47.6 mm) cue ball on coin-operated tables.
How much does a snooker ball weigh?
The WPBSA rules do not set a weight. They only say the balls should be of equal weight where possible, with no more than 3 g between the heaviest and lightest ball in a set.
Is the cue ball the same size as the other balls?
In regulation pool and snooker, yes. Coin-operated tables are the exception: they often use a slightly larger, heavier or magnetic cue ball (US) or a smaller one (UK) so the ball return can separate it.
Related reading: Billiards vs Pool vs Snooker · Chinese 8-Ball Table Size and Pockets · English Pool vs American Pool · Snooker Cue vs Pool Cue · Cue Tip Size and Hardness · How to Rack Pool Balls
Sources: WPA Recommended Equipment Specifications, section 16 (balls); WPA Rules of Heyball, effective 2025-08-16, Chapter II rule 3; WPBSA Official Rules of the Games of Snooker and English Billiards (Sept 2024), Section 1 Rule 2; CEB Material Norms 2024 (carom balls); World Eightball Pool Federation rules, section B (equipment, no ball size given). UK pool ball sizes and coin-op cue balls are the usual sets sold by ball makers and retailers, not a rule. This article contains no sponsored or affiliate links.