The length of an entire badminton court is 44 ft. Luckily you only have to cover your side of the net, so 22 ft! The width of the court you must cover is 17 ft in singles, and 20 ft per pair in doubles. The net which equally divides the length of the court should be 5 ft 1in high.
What is 'in' and 'out'?
Whether a particular shot is deemed 'in' or 'out' will differ depending if you are playing singles or doubles. In a singles match the court is often referred to as 'long and thin'. That is, the side tramlines and anything beyond are considered 'out'. This applies for every single shot in a game of singles. The situation in a doubles match is slightly different however.
For a serve in doubles the court is 'short and fat'. Roughly translated, that means that the back tramline is considered 'out', but the side tramline is deemed 'in' - the opposite to the situation in singles. However this only applies to the serve, as once you are in a rally in a doubles match, anything within the outer court line is considered 'in'. In both singles and doubles, the serve must always cross the front 'service line' however!