Carry On Bag for KLM Flight from LAX to Venice

I have used KLM to Amsterdam from the W Coast to travel onward within Europe a number of times. Vs Lufthansa, their weight allowance for both your personal item and carryon is an easier to meet 12 kg, vs 8 in premium. (Double check if it's changed this year, though, on their website.)
So you have to also keep in mind the weight of the empty suitcase, regardless of its dimension.

I can't remember if the sizer has the scale built in.
The July light expandable I have is 21.25" H x 14.17" W x 8.66" D (9.65" D when expanded). That could work? It's about 4 and 1/2 lbs.

My recommendation first is to go by the metric measurements not the inches. In my experience from a purchase a few years ago the companies round to get the inch measurement, sometimes up, sometimes down.

You do have to be cognizant of the total weight, which as mentioned is 12kilos/26.5# for your carry on and your personal item combined. When I have to fly a KLM leg I make sure I’m under that limit. I would in no way expect the agents to be less strict.

I purchased an Osprey Ozone in 2022 when I was flying a Delta Air France route. Air France has the same 26# limit. The Ozone weighs 4.5#. I’m currently in Scotland having arrived on a Spokane->Seattle->Amsterdam->Edinburgh itinerary with Delta/KLM. I brought the Ozone and for my personal item am using a Chico day pack that weighs a little over 7 ounces. My bags totaled 23.3# when I walked out of the house for the airport. They were not weighing bags as we boarded the Amsterdam flight but I met the guideline in case they did.

How much does the BagSmart rolling backpack weigh?

If you go with the Travel Pro, I’d only pick the International. I would not chance the size on the other 2.

Here's a couple of used/refurbished bags:
https://repack.eaglecreek.com/l/cargo-hauler-xt-215-wheeled-international-carry-on-duffel-discontinued/6a77b612-8409-4553-b5c7-242775e2666
Google AI says it's 55x35x20 (so well within the limit), has a 36L capacity and weighs 5lbs, 9oz (so a pound less than the Bagsmart).
Or this one is even less:
https://repack.eaglecreek.com/l/expanse-2-wheel-215-35l-international-carry-on-luggage/6a7a9a69-a6a6-43ab-b42f-58a7948effb4
55x35x20 with a 5cm expansion option to increase the capacity from 35L to 41L, 5lbs, 4oz.

It's very simple. You talk to nine people who have flown KLM and they tell you they had no problem.

You show up and get the one gate agent who follows the rules to the letter.

Airlines make a lot of money with oversize, and overweight, bags. Try to follow the rules the best you can.

I agree with going by the metric measurements for European carriers.

Thanks to all for such excellent advice and bag recommendations. I will make sure to adhere to the limits so there are no surprises.

Pam, the BagSmart is 6.6 lbs., so a bit heavy in comparison to those recommended here. I'll take that into consideration.

Not related to bag size per say but weight! Hit Paris with the 90-100 heat wave, one month in wonderfully fab weather on a cruise to Scandinavia, and landed in Phoenix at midnight with 106 degrees. Then home to 95 with 80% humidity.

I wore a very light jacket, very light sweater, LS T shirt, short sleeve T and pants and striped as I traveled on that particular 0travel day. Less weight in the carryon and I was comfortable at each destination within that 24-36 hour travel period. This is just me of course.

I also check seating chart. If flight is not fully booked, I feel more comfortable my bag will get on with no problem. Flying these past 6 years, have not had a problem. But it does just take the one agent!