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
| Bag | Outside size | Weight | Capacity | Fits | Buy |
|---|---|---|---|---|---|
| Osprey Farpoint 40 Travel Pack (Men's) | 21.7 × 13.8 × 9.1 in | 3.3 lb | 40 L | 3 of 8airlines | Amazon |
| Osprey Fairview 40 Travel Pack (Women's) | 21.7 × 13.8 × 9.1 in | 3.2 lb | 40 L | 3 of 8airlines | Amazon |
| Peak Design Travel Backpack 45LMost capacity | 22 × 13 × 9.5 in | 4.5 lb | 45 L | 3 of 8airlines | Amazon |
| Tortuga Pro Backpack 40L (formerly Travel Backpack Pro 40L) | 22 × 14 × 8 in | 4.4 lb | 40 L | 8 of 8airlines | Amazon |
| Cotopaxi Allpa 42L Travel PackLightest on this list | 22 × 14 × 11 in | 3.1 lb | 42 L | 0 of 8airlines | Amazon |
| NOMATIC Travel Bag 40L | 21 × 14 × 9 in | 3.4 lb | 40 L | 8 of 8airlines | Amazon |
| Aer Travel Pack 4 35L | 21.5 × 13.5 × 9 in | 3.9 lb | 35 L | 8 of 8airlines | Amazon |
“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
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
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
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
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
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
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
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
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.