Racket and string rules: what does the ITF allow?
TenisRaketi Editör Ekibi · Updated October 2026
Short answer
A racket may be up to 73.7 cm (29 in) long and 31.7 cm wide, with a string bed up to 39.4 × 29.2 cm. A vibration dampener may only sit outside the crossed strings. If a string breaks you may keep playing with that racket unless the event forbids it; one racket at a time, and no batteries.
In this guide
The ITF rules put only a few limits on a racket: its size, the shape of the string bed and what may be attached to it. Every racket sold in shops is within them; the rules matter most when you add something to a racket, or when something happens during a match.
Racket size limits
Measurement | Maximum |
|---|---|
Overall length | 73.7 cm (29 in) |
Overall width | 31.7 cm (12.5 in) |
String bed length | 39.4 cm (15.5 in) |
String bed width | 29.2 cm (11.5 in) |
A standard adult racket is 27 inches (68.6 cm); 27.5 and 28-inch "extended" rackets are within the limit too. How length plays is in the glossary, junior racket lengths in the junior racket guide. There is no limit on weight or balance; head size is limited only by the string bed limit.
ITF Appendix II (c).
What must the string pattern be like?
The string bed must be flat and made of crossed strings, interlaced alternately or bonded where they cross. The pattern must be generally uniform and not less dense in the centre than elsewhere. Both faces of the racket must play the same.
So a double layer of strings, strings on more than one plane, or a racket whose two faces play differently does not meet the rules. All the usual patterns, such as 16×19 or 18×20, are fine; how they differ is under string pattern.
ITF Appendix II (b); Rule 4, Cases 1–2.
Where can a vibration dampener go?
Only outside the crossed strings. A vibration dampener may be fitted outside the part of the string bed woven with crosses; in practice below the lowest cross, between the mains. A dampener in the middle of the strings is against the rules.
A dampener stops the string bed ringing and changes the sound; it does not meaningfully reduce the vibration from the frame to the arm. To protect your arm, a soft string and a lower tension do more: see the myths in the arm-friendly strings guide.
On court: Fit one for the sound, not for your arm; if you do, put it below the lowest cross.
ITF Rule 4, Case 3; Appendix II (d).
Can you keep playing if a string breaks?
Yes, unless the event forbids it. If a string breaks during a point you finish the point with that racket, and you may keep using it for the following points. Some events may forbid this.
If you want to change rackets you get no extra time for it: reasonable extra time is allowed for broken clothing or shoes, but the racket is excluded. Keep your spare racket ready. Playing on with broken strings for long strains the frame unevenly; more in the when to restring guide.
ITF Rule 4, Case 4; Rule 29 (b).
Can you use two rackets at once?
No. You may not use more than one racket at a time during play. Throwing your racket at the ball loses the point too, and so does deliberately and materially changing the shape of the racket while the ball is in play.
ITF Rule 4, Case 5; Rule 24 (j) and (k).
Lead tape, sensors and batteries
Nothing may be attached to a racket that could change its shape, its moment of inertia or any other property that affects play during a point. What is allowed:
- Parts that limit wear or vibration: head guard tape, a vibration dampener.
- Weight added to the frame only, to distribute weight: lead or tungsten tape.
- ITF-approved player analysis technology: sensors fitted to the handle, for example. During a match the data may only be looked at when coaching is allowed.
All of it must be reasonable in size and placement for its purpose. No energy source that could change how the racket plays (a battery, a solar cell) may be built into or attached to a racket.
ITF Appendix II (d); Rule 4, Case 6; Rule 30; Appendix III.
Frequently asked questions
What is the maximum length of a tennis racket?
29 inches (73.7 cm). A standard adult racket is 27 inches; 27.5 and 28-inch extended rackets are legal too.
Can a vibration dampener go in the middle of the strings?
No. Under the ITF rules a dampener may only sit outside the crossed strings; it usually goes below the lowest cross.
What happens if my string breaks in a match?
Unless the event forbids it, you may keep playing with the same racket. You get no extra time to change rackets, so keep your spare ready.
Is lead tape allowed?
Yes. Tape added to the frame to distribute weight is allowed, as long as it is reasonable in size and placement.
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