The dimensions of a tennis court are defined in the Rules of Tennis by the Intentional Tennis Federation (ITF). Rule 1 defines the dimensions of a singles tennis court. Rule 34 defines the dimensions of the doubles tennis court.
For practical purposes the vast majority of tennis courts are built to doubles dimensions, which allows for both singles and doubles.
The ITF Rules also define that the width of all lines on the tennis court shall be a minimum of 2.5cm and a maximum of 5cm except the baseline, which may be 10cm, and the centre service lines and centre mark, which shall be 5cm.
Courts should be oriented so that the sun inconveniences players as little as possible, with a north-south orientation preferred.
For international standard tournaments the overall area required is defined, dependant upon the event. However at club or recreational level, some suggested dimensions are given. As a guide the recommended minimun distances should be: the space behind each baseline 5.48m (18ft) and the space at the sides 3.05m (10ft).
To find out more, download the Tennis Infrastructure Planning Guide