Icelandair has specific rules and restrictions for carry-on baggage, including size and weight limits. According to the airline's currentpolicy (as of my knowledge cutoff date of September 2021), passengers areallowed to bring one carry-on bag and one personal item on board.
The maximum dimensions for the carry-on bag are 55cm x 40cmx 20cm (22in x 16in x 8in), and the maximum weight is 10kg (22lbs). Thepersonal item must fit under the seat in front of you and can be a purse,briefcase, or small backpack.
It's important to note that the carry-on bag and personalitem must fit within the weight and size limits, and if they do not, they mayneed to be checked and incur additional fees. It's always a good idea to checkthe airline's website for the most up-to-date information on baggage allowancesand restrictions before your flight.

As for top backpacks, here are six popular options:
1. Cabinzero Classic 44L Cabin Backpack: This backpack isgreat for those who want a spacious bag for a long trip. It has a durable outershell and plenty of compartments to keep your belongings organized.
2. Cabinzero Military Backpack 28L: If you're lookingfor a more compact backpack, this one is a good option. It has a sleek designand is made with military-grade materials, making it very durable.
3. Cabinzero Classic 28L Cabin Backpack: This backpack isanother great option for those who prefer a smaller bag. It's lightweight andperfect for a weekend getaway or a short trip. It also has plenty of pocketsand compartments to keep your things organized.
4. The Osprey Porter 46 is a popular backpack thatis designed to fit within most airlines' carry-on size restrictions. Itmeasures 56cm x 36cm x 23cm (22in x 14in x 9in), which is slightly larger thanIcelandair's maximum dimensions, but it has compressible sidewalls that allowit to fit within the limits.
5. The Eagle Creek Global Companion 40L is aversatile backpack that is designed for travel. It measures 56cm x 36cm x 23cm(22in x 14in x 9in), which is slightly larger than Icelandair's maximumdimensions, but it also has compressible sidewalls that allow it to fit withinthe limits.
6. The Kathmandu Litehaul 38L Carry-On Backpack isa compact and lightweight option that measures 55cm x 35cm x 23cm (21.6in x13.8in x 9.1in), making it a good fit for Icelandair's maximum carry-ondimensions.
It's worth noting that there are many backpack brands andmodels that could fit within Icelandair's carry-on baggage dimensions, so theseare just a few examples. As always, it's a good idea to check themanufacturer's specifications to ensure the backpack you choose fits within theairline's specific size and weight restrictions.
>> Read more: What backpack to buy for travelling?