Carry-On Gear Guide
Find Backpacks That Fit Your Airline
An Osprey Farpoint 40 is 9.1 inches deep, and Delta and United allow 9.
Size checker
Open Size Checker
Type in your bag’s dimensions, in inches or centimeters, and it lists the airlines it fits, with a warning wherever it is borderline.
Airline Carry-On Guides
Ryanair’s free bag is 40 x 30 x 20 cm, and none of the full-size packs we review fit it. Each airline’s guide lists the bags that do clear it.
Budget carriers
Major US carriers
Backpack Reviews
Dimensions come from the manufacturers, and what owners say comes from r/onebag and FlyerTalk.
Osprey Farpoint 40
40L · 9.1 in deep, 0.1 in over Delta and United
Cotopaxi Allpa 35L
35L · 8.3 in deep, fits Delta and United
Tortuga Pro 40L
40L · 0.2 in too wide for Delta and United
Nomatic 30L
30L · 8.5 in deep, fits Delta and United
Peak Design 45L
45L · 0.5 in too deep for Delta and United
Reference pages
Carry-On Compliance Checker
Inches or centimeters, any airline we cover.
Size Limits by Airline
Every airline’s cabin-bag limit in one table.
Best Carry-On Backpacks 2026
The bags we would pick for one-bag travel.
All Airline Guides
Start here if you already know your airline.
Travel Guides Hub
Packing lists and bag-versus-bag comparisons.
All Backpack Reviews
Specs and trade-offs for every bag we cover.
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