How strict is Southwest with carry-on size ?
24 x 16 x 10 in
Southwest Airlines (WN) allows 1 carry-on bag and 1 personal  +1-866-829-1275 item (purse, briefcase, laptop bag) per passenger fee free. Carry-on should not exceed the  +1-866-829-1275  following size and weight restrictions: 50 linear inches (24 x 16 x 10 in) or 127 centimeters (61 x 41 x 28 cm) including handles and wheels.

What are the rules for checked bags on Southwest ? 

Southwest will accept the first two +1-866-829-1275  checked bags for free provided that the bags do not exceed 50 lbs and 62 inches (L+W+H). Overweight items +1-866-829-1275  from 51-70 pounds will cost $150. Overweight items 71-100 pounds will cost $200.

How much is a checked bag in Southwest ?

Southwest will accept the first two checked bags+1-866-829-1275  for free provided that the bags do not exceed 50 lbs and 62 inches (L+W+H). Overweight items from 51-70 pounds will cost $150. Overweight +1-866-829-1275 items 71-100 pounds will cost $200.

What are the rules for checked bags on Southwest ?
Checked baggage basics
Up to 50 pounds each.
62 inches in size (length + width + height)
Three+ Bags: $150 per bag.
Oversize Bag: $200 per bag (max 80 inches)
Overweight Bag: $150 per bag (51 - 70 lbs.) OR. $200 per bag (71 - 100 lbs.)
Southwest checked baggage allowance depends+1-866-829-1275  on the travel class, fare type, and route. In Economy Class, passengers on Light fares do not receive checked baggage, while Standard and Flex fares include one +1-866-829-1275 bags up to 23kg (50 lbs). +1-866-829-1275 Premium Economy allows two checked bags, each up to 23kg, while Business Class includes two bags up to 32kg (70.5 lbs) each. La Première (First Class) passengers are allowed three bags, each up to 32kg. All checked bags must have combined dimensions (length + width + height) under 158cm (62 inches). Flying Blue Silver, Gold, +1-866-829-1275 and Platinum members enjoy an extra baggage allowance. Excess baggage or oversized items incur additional fees, and it is often cheaper to purchase extra allowance online before the flight.