What is the standard baggage weight limit for carry-on baggage?

Airlines set their own standard size limits for carry-on baggage, which is typically based on the size of the storage compartment and space under seats. Carry-on baggage that does not fit the limits set by airlines will need to be checked, especially on flights with limited cabin space for baggage.

Many airlines structure their carry-on baggage limits around the measurements of the bag, rather than the weight. For example, Southwest Airlines states that carry-on bags must be a maximum of 10 inches by 16 inches by 24 inches. Delta Airlines states that carry-on bags cannot be more than 45 linear inches and only personal items are allowed on planes with 50 seats or less, due to limited storage space.