Gregory Alpaca 40 vs. Tom Bihn Aeronaut 45L
Two carry-on travel backpacks, compared spec for spec.
Gregory Alpaca 40
| Capacity | 40 L |
| Weight | 1.2 kg |
| Dimensions | 57.9×33.8×28.7 cm |
| Airline fit | 1% |
| Price | $140 |
Feature by feature
| Gregory Alpaca 40 | Feature | Tom Bihn Aeronaut 45L |
|---|---|---|
| Storage | ||
| N | Compression | N |
| None | Expanded Capacity | None |
| 0 | Opening | 1 |
| side | Passport | side |
| N | Passthrough | N |
| Carry | ||
| removable | Backpack | hideable |
| N | Hip Belt | removable |
| N | Sternum Strap | removable |
| Inside | ||
| N | Laptop | N |
| 3 | Main Compartments | 5 |
| N | Organizer | N |
| Outside | ||
| × | Hard Shell | × |
| N | Rain-fly | N |
| N | Water Bottle Holder | N |
| Y | Water Resistant | Y |
| Material | |
| 40% Recycled 900D Polyester Ripstop with TPU Weather resistant coating | 1050 denier ballistic nylon OR ultralight 400d Halcyon/420d nylon ripstop 200 denier Halcyon/nylon ripstop fabric lining |
Tom Bihn Aeronaut 45L
| Capacity | 45 L |
| Weight | 1.4 kg |
| Dimensions | 56×36×23 cm |
| Airline fit | 45% |
| Price | $340 |
Key differences between the Gregory Alpaca 40 and Tom Bihn Aeronaut 45L
- Opening: Other on the Gregory Alpaca 40; Clamshell on the Tom Bihn Aeronaut 45L.
- Backpack straps: Removable on the Gregory Alpaca 40; Hideable on the Tom Bihn Aeronaut 45L.
- Hip belt: No on the Gregory Alpaca 40; Removable on the Tom Bihn Aeronaut 45L.
- Sternum strap: No on the Gregory Alpaca 40; Removable on the Tom Bihn Aeronaut 45L.
- Main compartments: 3 on the Gregory Alpaca 40; 5 on the Tom Bihn Aeronaut 45L.
Both have: passport pocket, water resistant.
Which airlines take each bag as a carry-on
We checked both bags against the carry-on size limits of 189 airlines. 2 accept both. 0 accept only the Gregory Alpaca 40, and 83 accept only the Tom Bihn Aeronaut 45L.
Only the Tom Bihn Aeronaut 45L fits
Adria Airways, Aegean Airlines, Air Asia, Air Astana, Air Europa, Air Koryo, Air Macau, Air New Zealand, Air Nostrum, Air Tahiti Nui, Air Wisconsin, AirAsiaX, Alaska Airlines, Allegiant Air, American Airlines, Atlas Global, Avianca , Azul Linhas, Bahamasair, Bangkok Airways, Biman Bangladesh, British Airways, Cambodia Angkor Air, Cathay Pacific, Cebu Pacific, China Airlines, China Southern, CommutAir, Conviasa, Copa Airlines, Cubana de Aviacion, Delta Airlines, Dragonair, EL AL, EVA Air, Finnair, Frontier Airlines, Garuda Indonesia, Hainan Airlines, Hawaiian Airlines, Hong Kong Airlines, Iran Aseman Air, Island Air, Jet2, jetBlue Airways, Jetstar Airways, Jetstar Asia, Korean Air, Kulula, Kuwait Air, Malaysia Airlines, Mango, Middle East Airlines, Monarch Airlines, Onur Air, PenAir, Philippine Airlines, Qantas Airways, Republic Airways, Royal Air Morocco, Saudi Arabian Airlines, Sichuan Airlines, SilkAir, Silver Airways, Singapore Airlines, Skywest, Inc., South African Airways, Southwest Airlines, SpiceJet, Spirit Airlines, SriLankan Airlines, Sun Country, TAAG Angola, TAM Airlines, Thai Airways, Trans States, Travel Service Airlines, United Airlines, Ural Airlines, Uzbekistan Air, Vietnam Airlines, Virgin Atlantic, WOW Airlines.
Gregory Alpaca 40 vs. Tom Bihn Aeronaut 45L: which should you pack?
The Tom Bihn Aeronaut 45L carries 5L more than the Gregory Alpaca 40 (40L vs. 45L), while the Gregory Alpaca 40 is the lighter pack at 1.2kg (vs. 1.4kg). For carry-on flexibility, the Tom Bihn Aeronaut 45L fits 45% of the airlines we track — the higher of the two. If you prioritise packing volume, choose the Tom Bihn Aeronaut 45L; if you want to travel lighter, the Gregory Alpaca 40 is the better call.