4.5
Women’s-Specific Trial Ball
- Smaller dimensions
- Same weight as size 5
- Developed with Gilbert
- Designed for elite performance
- Currently being trialed
RFC EXPLAINS
Why Is Women’s Rugby Trialing a Size 4.5 Ball?
World Rugby is testing a women’s-specific rugby ball with smaller dimensions but the same weight as a traditional size 5. Here’s what is changing, why it is being tested and what happens next.
4.5Trial ball size
SameWeight as size 5
2026Elite 15s WXV trial
01THE SHORT ANSWER
Why is women’s rugby trialing a size 4.5 ball?
World Rugby is testing whether a ball designed specifically for female players can provide greater control and accuracy while retaining the performance required for elite rugby.
The bespoke size 4.5 ball has smaller dimensions than a traditional size 5, but importantly, it has the same weight.
Women’s rugby has not permanently switched to a smaller ball. This is an ongoing World Rugby trial.
02WHAT’S DIFFERENT?
Size 4.5 vs Size 5
This is not simply a junior ball being introduced into elite women’s rugby. World Rugby describes the trial product as a bespoke women’s-specific ball developed with Gilbert.
VS
5
Traditional Senior Ball
- Larger dimensions
- Standard senior rugby ball
- Traditionally used in elite women’s rugby
- Established match-ball format
- Remains the normal senior standard
KEY DIFFERENCESmaller dimensions. Same weight.
03WHY TEST IT?
Could equipment designed for female players improve performance?
That is the central question behind World Rugby’s size 4.5 ball trial.
Handling affects almost every part of attacking rugby. Players must control the ball while passing, catching, carrying, offloading and operating under defensive pressure.
World Rugby says feedback from earlier trials indicated that players experienced greater control and accuracy with the women’s-specific size 4.5 ball.
The governing body also said players felt the ball provided a better platform for showcasing handling skills, with no reported adverse impact on kicking.
THE QUESTION BEING TESTED
Can a rugby ball designed specifically with female players in mind provide a better platform for skill execution at elite level?
RFC reporting: Rugby Fan Central contacted Gilbert Rugby for additional information about the development and testing of the women’s-specific size 4.5 ball. Gilbert had not responded by the time of publication.
04HOW WE GOT HEREEARLY TRIALS DOMESTIC TESTING 2026 2026
The size 4.5 trial did not begin at WXV
World Rugby has expanded the women’s-specific ball trial in stages, moving from developmental and domestic environments into elite international competition.
U18 & U20 International Rugby
World Rugby tested the women’s-specific ball in age-grade international competitions as part of the early development process.
Spain & Colombia
The trial also moved into domestic competition environments in Spain and Colombia, alongside testing in elite club training.
HSBC SVNS
The experiment reached elite international sevens when World Rugby expanded the size 4.5 trial into the 2026 HSBC SVNS Series.
WXV Global Series
WXV takes the experiment into elite international 15-a-side rugby, giving World Rugby another environment in which to assess the ball.
WHY THE STEP-BY-STEP APPROACH MATTERS
Each stage exposes the ball to a different level or format of rugby. That gives World Rugby more evidence before deciding whether the trial should be expanded, changed or ended.
05THE EVIDENCE
What is World Rugby measuring?
The trial is about more than whether players simply prefer the feel of the ball. World Rugby says it will examine several different forms of evidence.
Player Feedback
How players experience passing, catching, carrying, control and kicking with the ball.
Injury Surveillance
Player-welfare information is being monitored during the trial. World Rugby has not claimed that the smaller ball reduces injuries.
Shape of the Game
Match data can help determine whether the different ball affects how elite women’s rugby is actually played.
06WHAT WE KNOW
Evidence vs assumption
The size 4.5 trial has generated interest, but it is important to separate what World Rugby has actually confirmed from conclusions that have not yet been established.
✓ What World Rugby has confirmed
The ball is size 4.5.
It has the same weight as a size 5.
It was developed with Gilbert.
Earlier player feedback has been positive.
The trial has expanded into elite sevens and 15s.
✕ What has NOT been established
That the size 4.5 ball is definitively better.
That it reduces injuries.
That all women’s rugby will adopt it.
That the traditional size 5 is being eliminated.
That a permanent change has been approved.
07THE CURRENT TEST
Why WXV 2026 matters
The 2026 WXV Global Series Challenger moves the experiment into elite international 15-a-side rugby.
Fifteens creates different patterns of possession, kicking, contact, set piece and phase play from sevens, giving World Rugby another environment in which to evaluate the ball.
World Rugby says it will consider evidence from WXV alongside information gathered through the sevens trial before assessing what should happen next.
CURRENT STATUSELITE INTERNATIONAL TRIALNo permanent change announced
08THE BIGGER QUESTION
Why this matters beyond the rugby ball
The experiment raises a broader question about equipment in women’s sport.
Should equipment traditionally used across rugby automatically remain the best option for female athletes — or should alternatives be tested?
World Rugby’s trial does not assume that smaller equipment is better. Instead, it tests whether equipment designed specifically with female players in mind can provide a better platform for performance.
The evidence — not the assumption — will determine what happens next.
09QUICK ANSWERS
Women’s rugby size 4.5 ball FAQ
Do women normally use a smaller rugby ball?
No. Senior women’s rugby has traditionally used the standard size 5. The size 4.5 ball is currently being tested in selected women’s competitions.
Is the size 4.5 ball lighter than a size 5?
No. World Rugby says its bespoke women’s-specific size 4.5 trial ball has the same weight as a standard size 5.
Is a size 4.5 just a junior rugby ball?
No. World Rugby describes the trial ball as a bespoke women’s-specific product developed with Gilbert while retaining advanced aerodynamic and technological features.
Why is World Rugby testing it?
World Rugby is investigating whether the different dimensions can improve control and accuracy and provide a better platform for players to showcase their skills.
Has World Rugby permanently changed the women’s ball?
No. This remains a trial. No permanent switch from size 5 to size 4.5 has been announced.
Could size 4.5 eventually become permanent?
It is possible, but no decision has been made. World Rugby says it will assess player feedback, injury surveillance and shape-of-game data before determining the next steps with the wider women’s game.
THE BOTTOM LINE
Women’s rugby has not switched to a smaller ball.
World Rugby is trialing a women’s-specific size 4.5 rugby ball developed with Gilbert.
It has smaller dimensions but the same weight as a traditional size 5.
Early player feedback has been positive, and the experiment has now progressed into elite international sevens and 15s.
What happens after that will depend on the evidence.
STATUS: TRIAL IN PROGRESS
10PRIMARY SOURCES
Sources & further reading
This RFC Explains guide is based primarily on information published by World Rugby and Gilbert Rugby about the women’s-specific ball trial.
- World Rugby — Women’s-specific ball trial extended to WXV Global Series
- World Rugby — Size 4.5 trial expanded to HSBC SVNS
- Gilbert Rugby — Background to the women’s-specific ball trial
RFC REPORTING NOTE
Rugby Fan Central contacted Gilbert Rugby for additional comment about the development and testing of the women’s-specific size 4.5 ball. No response had been received at the time this guide was published.
Last updated: September 6, 2026