The number of laptops you are allowed to bring on a plane is determined by the airline's individual policies as well as any international travel regulations. Typically, most airlines permit passengers to bring one carry-on bag and one personal item into the aircraft.
If you are carrying multiple laptops, they would need to fit into your allowed carry-on or personal item. You may need to ensure that each laptop fits within the airline's size and weight restrictions for carry-on bags.
It is always recommended to check with your airline for their specific policies regarding the number of bags, weight limits, and any additional fees or restrictions that may apply. Additionally, some countries may have restrictions on the number of electronics or laptops you can bring with you, so it is always best to check the customs regulations of your destination country.