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CarryOnAtlas

Best Carry-On Travel Backpacks

A 35–45 liter travel backpack replaces a roller bag for one-bag travel. These fit the US carry-on limit when packed sensibly.

How we picked

These packs are sold as carry-on size. We list the maker’s outside dimensions and check them against eight US airlines’ carry-on limits. Soft packs flex, so a bag that is a fraction over on paper often fits when not overstuffed, but the strictest gates measure what they see.

At a glance

Best Carry-On Travel Backpacks
BagOutside sizeWeightCapacityFitsBuy
Osprey Farpoint 40 Travel Pack (Men's)21.7 × 13.8 × 9.1 in3.3 lb40 L3 of 8airlinesAmazon
Osprey Fairview 40 Travel Pack (Women's)21.7 × 13.8 × 9.1 in3.2 lb40 L3 of 8airlinesAmazon
Peak Design Travel Backpack 45LMost capacity22 × 13 × 9.5 in4.5 lb45 L3 of 8airlinesAmazon
Tortuga Pro Backpack 40L (formerly Travel Backpack Pro 40L)22 × 14 × 8 in4.4 lb40 L8 of 8airlinesAmazon
Cotopaxi Allpa 42L Travel PackLightest on this list22 × 14 × 11 in3.1 lb42 L0 of 8airlinesAmazon
NOMATIC Travel Bag 40L21 × 14 × 9 in3.4 lb40 L8 of 8airlinesAmazon
Aer Travel Pack 4 35L21.5 × 13.5 × 9 in3.9 lb35 L8 of 8airlinesAmazon

“Fits” tests the maker’s published outside size against the carry-on limit of Delta, American, United, Southwest, JetBlue, Alaska, Frontier, Allegiant, using the same math as our bag size checker.

The picks

1

Osprey Farpoint 40 Travel Pack (Men's)

21.7x13.8x9.1 in (55x35x23 cm), within the 22x14x9 in US carry-on limit, and Osprey says it is sized to meet domestic carry-on requirements.

Outside size
21.7 × 13.8 × 9.1 in55 × 35 × 23 cm
Weight
3.3 lb1.5 kg
Capacity
40 L

Laptop sleeve up to 16 in.

Carry-on limit check

  • Delta: Too big
  • American: Too big
  • United: Too big
  • Southwest: Fits
  • JetBlue: Too big
  • Alaska: Too big
  • Frontier: Fits
  • Allegiant: Tight fit
Size limit: 21.7 by 13.8 by 9.1 inches (55 cm by 35 cm by 23 cm) 21.7 in55 cm 13.8 in35 cm 9.1 in23 cm
2

Osprey Fairview 40 Travel Pack (Women's)

Same 21.7x13.8x9.1 in (55x35x23 cm) body as the Farpoint 40, within 22x14x9 in, with a women's-specific fit.

Outside size
21.7 × 13.8 × 9.1 in55 × 35 × 23 cm
Weight
3.2 lb1.5 kg
Capacity
40 L

Women's-specific harness; laptop sleeve up to 16 in.

Carry-on limit check

  • Delta: Too big
  • American: Too big
  • United: Too big
  • Southwest: Fits
  • JetBlue: Too big
  • Alaska: Too big
  • Frontier: Fits
  • Allegiant: Tight fit
Size limit: 21.7 by 13.8 by 9.1 inches (55 cm by 35 cm by 23 cm) 21.7 in55 cm 13.8 in35 cm 9.1 in23 cm
3Most capacity

Peak Design Travel Backpack 45L

22x13x9.5 in (56x33x24 cm) in its standard 35L mode, which is right at the 22x14x9 in limit (0.5 in deeper); expanding to 45L adds depth, so keep it unexpanded for strict airlines.

Outside size
22 × 13 × 9.5 in56 × 33 × 24 cm
Weight
4.5 lb2 kg
Capacity
45 L

Expanded 45L mode: 56x33x29 cm (22x13x11 in).

Carry-on limit check

  • Delta: Too big
  • American: Too big
  • United: Too big
  • Southwest: Fits
  • JetBlue: Too big
  • Alaska: Too big
  • Frontier: Fits
  • Allegiant: Tight fit
Size limit: 22 by 13 by 9.5 inches (56 cm by 33 cm by 24 cm) 22 in56 cm 13 in33 cm 9.5 in24 cm
4

Tortuga Pro Backpack 40L (formerly Travel Backpack Pro 40L)

22x14x8 in (55x35x20 cm), within the 22x14x9 in US limit and close to common 55x40x20 cm international limits, at a full 40L.

Outside size
22 × 14 × 8 in55 × 35 × 20 cm
Weight
4.4 lb2 kg
Capacity
40 L

Fits up to a 16 in laptop.

Carry-on limit check

  • Delta: Tight fit
  • American: Tight fit
  • United: Tight fit
  • Southwest: Fits
  • JetBlue: Tight fit
  • Alaska: Tight fit
  • Frontier: Fits
  • Allegiant: Tight fit
Size limit: 22 by 14 by 8 inches (56 cm by 36 cm by 20 cm) 22 in56 cm 14 in36 cm 8 in20 cm
5Lightest on this list

Cotopaxi Allpa 42L Travel Pack

22x14 in footprint fits the US limit, but the published 11 in depth is 2 in over 22x14x9, so it only fits a sizer when it isn't fully packed or the airline is lenient.

Outside size
22 × 14 × 11 in56 × 36 × 27 cm
Weight
3.1 lb1.4 kg
Capacity
42 L

Carry-on limit check

  • Delta: Too big
  • American: Too big
  • United: Too big
  • Southwest: Too big
  • JetBlue: Too big
  • Alaska: Too big
  • Frontier: Too big
  • Allegiant: Too big
Size limit: 22 by 14 by 11 inches (56 cm by 36 cm by 28 cm) 22 in56 cm 14 in36 cm 11 in28 cm
6

NOMATIC Travel Bag 40L

21x14x9 in, within the 22x14x9 in US carry-on limit, and it switches between backpack and duffel carry.

Outside size
21 × 14 × 9 in53 × 36 × 23 cm
Weight
3.4 lb1.6 kg
Capacity
40 L

Converts between backpack and duffel; laptop compartment up to 16 in.

Carry-on limit check

  • Delta: Tight fit
  • American: Tight fit
  • United: Tight fit
  • Southwest: Fits
  • JetBlue: Tight fit
  • Alaska: Tight fit
  • Frontier: Fits
  • Allegiant: Fits
Size limit: 21 by 14 by 9 inches (53 cm by 36 cm by 23 cm) 21 in53 cm 14 in36 cm 9 in23 cm
7

Aer Travel Pack 4 35L

21.5x13.5x9 in (54.5x34x23 cm), within the 22x14x9 in US limit, in a structured 35L pack.

Outside size
21.5 × 13.5 × 9 in55 × 34 × 23 cm
Weight
3.9 lb1.8 kg
Capacity
35 L

Fits up to a 16 in laptop.

Carry-on limit check

  • Delta: Tight fit
  • American: Tight fit
  • United: Tight fit
  • Southwest: Fits
  • JetBlue: Tight fit
  • Alaska: Tight fit
  • Frontier: Fits
  • Allegiant: Fits
Size limit: 21.5 by 13.5 by 9 inches (55 cm by 34 cm by 23 cm) 21.5 in55 cm 13.5 in34 cm 9 in23 cm

How many liters fit in a carry-on?

A bag that fills the whole 22 × 14 × 9 in box holds about 45 liters. Real packs lose a few liters to padding and shape, so 35–42 L is the practical carry-on range. For international airlines with 55 × 40 × 20 cm limits, stay closer to 35 L.

Frequently asked questions

Is a 40L backpack a carry-on?
Usually yes. Most 40 L travel packs are built to about 22 × 14 × 9 in, the US carry-on limit. It counts as your carry-on, not your personal item.
Is a 45L backpack too big for a carry-on?
Often it is right at the limit. Peak Design’s 45L, for example, is 9.5 in deep fully expanded; compress it to its 35 L mode to be safe.
Can I bring a travel backpack and a personal item?
Yes on most US airlines with a standard fare: the travel pack is your carry-on and a smaller bag goes under the seat.

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