What should I pay attention to with regard to size and weight restrictions for hand luggage?
Be aware of the IATA recommendations! IATA stands for International Air Transport Association. As various airlines have different rules regarding hand luggage, this umbrella organisation states a recommendation.
Currently, the maximum recommended size for hand luggage is
Height 56 cm x Width 45 cm x Depth 25 cm.
The information for maximum weight depends on the airline and is somewhere between 5 kg and 23 kg.
Therefore: Please get information about your airline’s respective regulations before your trip.