Size 5 is the full-size ball; younger age groups use smaller sizes according to their union or competition's age-grade rules. There is no single age chart that applies everywhere, so confirm the assigned size with your club before buying and compare match or training use separately.
The right size is the one assigned to the player’s age grade and competition. Ball size names are useful when comparing products, but they do not create one universal age schedule for every rugby union or format.
Compare sizes, then check the age-grade rule
| Ball size | General use | What to confirm |
|---|---|---|
| Size 3 | Smaller youth ball | The age-grade rule for the team and format |
| Size 4 | Intermediate youth ball | Whether the competition uses size 4 for that age group |
| Size 5 | Full-size ball for adult rugby | Any competition-specific equipment requirement |
These are broad buying cues, not fixed age cut-offs. Age-grade policies can differ between unions and formats. Ask the club, school or union which size the team uses, especially when the ball is for a match or organized training.
World Rugby Law 2 describes the standard ball as oval with four panels. It gives a weight of 410–460 g and a starting pressure of 65.71–68.75 kPa (9.5–10 psi); match organizers may permit smaller balls. The law does not publish a universal youth age chart.
Size is separate from match or training use
Two balls can share a size while being sold for different uses. Decide the team size first, then compare the maker’s match and training models by the exact specification, intended surface and practice volume. See rugby match balls vs training balls for that separate decision.
For the equipment differences between touch and tag rugby, see touch vs tag rugby.
For a kicking setup, see rugby kicking tees and the place-kick rule. Browse rugby balls.
Sources
Common questions
What size rugby ball does an adult use?
Size 5 is the full-size ball used in adult rugby. A competition may set its own requirements, so check the rules for your format.
What size rugby ball should a child use?
The assigned size depends on the player's age grade and the governing union. Ask the club or school which size its teams use before ordering.
Are size 3 and size 4 rugby balls for different age groups?
They are smaller ball sizes used in youth rugby, but the age cut-offs vary. Use the local age-grade rules rather than an age chart from another union.
How much air should I put in a rugby ball?
For the standard full-size match ball, World Rugby Law 2 gives a starting pressure of 9.5–10 psi. Follow the maker's guidance for other sizes and practice balls.