Tennis court dimensions and lines: singles, doubles and the service box
TenisRaketi Editör Ekibi · Updated October 2026
Short answer
A tennis court is 23.77 m long; 8.23 m wide for singles and 10.97 m for doubles. The service line is 6.40 m from the net, and the net is 0.914 m high in the centre and 1.07 m at the posts. In singles the 1.37 m alley along each side is out.
In this guide
This guide covers the court measurements in the ITF rules, which lines count in which match, and the layout around the court.
Tennis court dimensions
Measurement | Value |
|---|---|
Court length | 23.77 m |
Singles width | 8.23 m |
Doubles width | 10.97 m |
Alley (each side) | 1.37 m |
Service line to net | 6.40 m |
Net height, centre | 0.914 m |
Net height, at the posts | 1.07 m |
Posts outside the doubles court | 0.914 m |
All measurements are taken to the outside of the lines. Baselines may be up to 10 cm wide, the centre service line and centre mark are 5 cm, the other lines 2.5–5 cm. A 10 cm centre mark divides each baseline.
ITF Rule 1; Appendix IX.
Which lines count in singles?
In singles the two outer sidelines do not count. The 1.37 m strip along each side is the alley, and it is only in play in doubles. In singles a ball in the alley is out; in doubles the same ball is in.
The service boxes are the same in both: they sit between the singles sidelines. So in doubles a serve into the alley is a fault too.
On court: In singles watch the inner sideline; a ball in the alley is out.
ITF Rule 1; Rule 17.
The lines are part of the court
A ball that touches a line counts as touching the court that line bounds. As measurements are taken to the outside of the lines, the whole line is inside the court. Confusing line calls are in the Whose point? guide.
ITF Rule 12.
Net and posts
The net fills the whole space between the posts, with a mesh small enough that the ball cannot pass through. A white strap holds it down in the centre and a white band covers the top. When singles is played with a doubles net, two singles sticks, 0.914 m outside the singles court, hold the net at 1.07 m. The net outside the sticks and the main posts then count as permanent fixtures.
ITF Rule 1; Rule 2.
The court's permanent fixtures
The back and side stops, spectators, stands, the umpire's chair, officials in their places and ball persons are the court's permanent fixtures. If the ball in play hits one after landing in the correct court, the player who hit it wins the point; if it hits one before bouncing, that player loses the point.
ITF Rule 2; Rule 13.
Junior courts: red and orange
Competitions for 10 and under can use smaller courts:
Court | Length | Width | Net at centre |
|---|---|---|---|
Red | 10.97–12.80 m | 4.27–6.10 m | 0.80–0.84 m |
Orange | 17.68–18.29 m | 6.10–8.23 m | 0.80–0.91 m |
Green | Full court | Full court | 0.914 m |
Which ball and racket fit which age is in the junior racket guide and the ball guide.
ITF Appendix VIII.
How much space around the court?
The minimum clearances the ITF recommends:
Use | Behind the baseline | Outside the sidelines |
|---|---|---|
Club and recreational | 5.48 m | 3.05 m |
International events | 6.40 m | 3.66 m |
Indoors, at least 9 m from the surface to the ceiling above the net is recommended.
ITF Appendix X.
Frequently asked questions
How big is a tennis court?
23.77 m long; 8.23 m wide for singles and 10.97 m for doubles.
How high is a tennis net?
91.4 cm in the centre and 107 cm at the posts.
Is a ball in the alley in during singles?
No. The alley is only in play in doubles; in singles a ball in the alley is out.
In doubles, is a serve into the alley good?
No, it is a fault. The service boxes are the same in singles and doubles and do not include the alley.
More guides on this topic
- Tennis rules: the basics for beginnersPoints in tennis go 15, 30, 40; you win a game with four points and a two-point lead, and a set with six games and a two-game lead, with a tie-break at 6-6. You serve from behind the baseline into the diagonal box and you get two serves. A ball that touches the line is in.
- Whose point? The most confused tennis rulesA ball that touches the line is in. You lose the point if you catch a ball going out, if the serve hits you before it bounces or if you volley the serve. Your racket may cross the net but not touch it. A ball that goes around the net post is good.
- How tennis scoring works: 15-30-40, advantage, sets and tie-breaksPoints in a game go 0, 15, 30, 40 and the fourth point wins it; after 40-40 you need two points in a row. The first to six games with a lead of two wins the set, with a tie-break at 6-6. In a tie-break the first to seven with a lead of two wins, and the serve changes every two points after the first.
- Tennis serve rules: sides, two serves, lets and foot faultsEvery game starts with a serve from the right half, from behind the baseline into the diagonal box; you switch halves after each point. You get two serves, and two faults make a double fault. A let does not cancel an earlier fault. Tossing and not hitting is not a fault; swinging and missing is.
- Tennis ball types: the ITF ball types and court paceThe ITF approves three ball types: Type 1, a fast ball for slow courts; Type 2, a medium ball for most courts; and Type 3, a bigger, slower ball for fast courts. All weigh 56–59.4 g; Type 3 is 7.00–7.30 cm across, the others 6.54–6.86 cm. Juniors have red, orange and green balls.
- Racket and string rules: what does the ITF allow?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.
- Doubles tennis rules: serving order, receiving and positionsIn doubles each team decides at the start of a set who serves first; the serve then rotates between teams and between partners. On the receiving team the players take turns, point by point. The alley is in during rallies and out on the serve. Players may stand anywhere on their side; both partners may not hit the ball.
- Time, breaks, coaching and officials in a tennis matchThe warm-up is up to 5 minutes. Up to 25 seconds are allowed between points, 90 seconds at a change of ends and 120 seconds between sets. There is no extra time to recover condition; a 3-minute medical time-out may be allowed for a treatable condition. Coaching is never allowed during a point. The chair umpire decides questions of fact, the referee questions of law.
- The match on TV: what is different at the ATP, WTA and Grand SlamsThe ATP, the WTA and the Grand Slams play by the ITF Rules of Tennis and add their own regulations. The differences you see on TV: an electronic system instead of line judges at the ATP and WTA, penalties for time violations, coaching from the coaches' box, a 10-point final-set tie-break at the Grand Slams and no-ad games in doubles.