23.77 m
A regulation tennis court is 23.77 metres long
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Photo: Sebleouf · CC BY-SA 4.0
The short answer
The ITF specifies a court length of 78 feet, given as 23.77 metres. That baseline-to-baseline length is the same for standard singles and doubles.
Why it's true
A tennis court does not get longer when four players replace two. Rule 1 of the ITF Rules of Tennis sets one length for the rectangle and separate widths for singles and doubles. The familiar 23.77 metres measures the playing court, not the fenced enclosure, spectator space, or distance between players standing behind their baselines.
The imperial equivalent explains the apparently unusual decimal. The rule gives 78 feet alongside 23.77 metres. Converting 78 feet produces 23.7744 metres, so the published metric number is rounded. It is better to quote the paired official dimensions than imply that tennis was designed around a specially chosen centimetre.
By the numbers
23.77 m
Standard court length
78 ft
Imperial length in Rule 1
6.40 m
Net to service line
How we know
Rule 1, titled The Court, supplies the measurement directly. It describes a rectangle 78 feet long, identifies the lines at its ends as baselines, and places a net across its width. The same rule requires measurements to be taken to the outside of the lines. That last instruction matters when marking a court: the paint is part of the measured playing area.
The 2026 ITF rulebook also includes a court plan and marking guidance. Those drawings help distinguish the baseline from the nearer service line. The service line lies 21 feet, or 6.40 metres, from the net on each side. A court therefore contains several prominent transverse lines, but only the two outer end lines establish its full length.
Worth remembering
- Standard singles and doubles share the same baseline length.
- The 23.77 metre figure is paired with 78 feet.
- Court length excludes runoff outside the baselines.
In context
A ball may be played while its striker is outside the painted rectangle. The landing area, rather than the player’s standing position, usually decides whether a rally shot is in. Service foot-fault rules add separate restrictions at the start of a point.
A closer look
The rectangle is not the whole venue
Players regularly move beyond the baseline to return deep shots. The area behind it is not an extension of the legal landing zone: it is space in which a player may stand and move while playing the ball. A shot that first bounces beyond the opponent’s baseline is still out, even if the receiver is positioned much farther back.
This distinction explains why television images can make courts look different in size. A stadium with generous runoff and a small public enclosure can contain the same marked rectangle. Camera height and lens position alter its apparent proportions too. You cannot determine regulation length from the amount of visible paving or the distance to the back fence.
What the length changes tactically
A baseline rally asks each player to send the ball across the net and into a finite landing area. A deep ball lands near the far baseline and can push the receiver backward; a short ball lands nearer the net and invites a forward approach. These descriptions refer to position within the same fixed court, not different categories of court length.
The length also works together with width. A diagonal path across the singles rectangle is longer than a straight path running parallel to a sideline. That geometric difference helps explain why crosscourt rallies can offer more distance in which a ball may descend. It does not guarantee that a crosscourt shot is safe: speed, spin, height, and contact position still determine where it lands.
Another useful distinction is between a ball landing long and a player reaching beyond the baseline. During a rally, there is no requirement to strike from inside the court. A receiver can retreat well behind the line, contact the ball there, and send a legal return into the opponent’s court. The length specification fixes where a bounce is accepted, not a cage around the athletes. This is why court diagrams alone cannot describe the full movement demands of a match, even though they are sufficient to establish the official baseline-to-baseline dimension.
Related facts
See how a format change alters the legal landing area. Doubles tennis uses a wider court than singles.
Explore another measurable constraint on a ball crossing a net. A tennis net is lower at the centre than at its supports.
Look at the full rectangle surrounding basketball’s internal markings. A standard FIBA basketball court measures 28 by 15 metres.
Explore another equipment specification that is easy to quote but needs careful units. A regulation table tennis ball has a specified diameter of forty millimetres.
Key terms
- Court length
- Baseline-to-baseline distance: 23.77 metres.
- Baseline
- Back boundary line at either end of the court.
People also ask
Does doubles use a longer court?
No. Standard doubles retains the 23.77 metre length. Its wider sidelines add lateral space, while the baselines stay in the same places. A facility can therefore host both formats on one painted rectangle without moving either end line.
Are the lines included in the measurement?
Yes. ITF Rule 1 says court measurements are taken to the outside of the lines. Separately, Rule 12 says a ball touching a line is regarded as touching the court bounded by that line. Measurement and line calling are related but distinct instructions.
Is every tennis format played on this length?
No. The claim concerns the standard court described in Rule 1. The ITF also provides modified competition arrangements for young children, including smaller courts. Those adaptations do not contradict the full court specification; they are separately described formats.
Where does the service box end?
The service line is 6.40 metres from the net, parallel to it. The centre service line divides the space into two service courts. A legal first service bounce belongs in the diagonally opposite service court, not simply anywhere inside the full baseline rectangle.
Why should a club measure rather than copy a photograph?
A photograph does not reveal reliable scale, line edges, or perspective. Measuring the prescribed rectangle and checking its geometry is more dependable. Court construction also requires suitable surrounding space, surface preparation, and equipment, none of which is established by the length number alone.
