Ortlieb Commuter Daypack High Visibility vs. Tom Bihn Synapse 25

Two carry-on travel backpacks, compared spec for spec.

Ortlieb Commuter Daypack High Visibility

Front facing view of the Ortlieb Commuter Daypack High Visibility
Capacity21 L
Weight0.86 kg
Dimensions50×30×15.5 cm
Airline fit92%
Price$250

Feature by feature

Ortlieb Commuter Daypack High VisibilityFeatureTom Bihn Synapse 25
Storage
N Compression N
None Expanded Capacity None
2 Opening 0
N Passport front
N Passthrough N
Carry
Y Backpack Y
removable Hip Belt removable
removable Sternum Strap removable
Inside
15in Laptop 15in
1 Main Compartments 6
Y Organizer Y
Outside
× Hard Shell ×
N Rain-fly N
N Water Bottle Holder 1, front
Y Water Resistant Y
Material
PS50CX200 denier Halcyon/nylon ripstop fabric lining 400 denier nylon lower back

Tom Bihn Synapse 25

Front facing view of the Tom Bihn Synapse 25
Capacity25 L
Weight0.8 kg
Dimensions51×34×23 cm
Airline fit71%
Price$250

Key differences between the Ortlieb Commuter Daypack High Visibility and Tom Bihn Synapse 25

Both have: backpack straps, hip belt, sternum strap, laptop sleeve, built-in organizer, water resistant.

Which airlines take each bag as a carry-on

We checked both bags against the carry-on size limits of 189 airlines. 134 accept both. 39 accept only the Ortlieb Commuter Daypack High Visibility, and 0 accept only the Tom Bihn Synapse 25.

Only the Ortlieb Commuter Daypack High Visibility fits

Air Baltic, Air China, Air Malta, Air Niugini, Air Serbia, Air Seychelles, Asiana Airlines, ATA Airlines, Belavia, Blue Air, Bulgaria Air, China Eastern, Emirates Airlines, Enter Air, Etihad Airways, flybe, Icelandair, InselAir, Juneyao Airlines, Liat Airlines, Luxair, Meridiana Fly, Nordwind Airlines, Pakistan International, Qatar Airways, Royal Brunei Airlines, Ryanair, S7, Shandong Airlines, Shenzhen Airlines, Sun Express, TAP Air Portugal, TAROM, Tianjin Airlines (A320 & E190), TUI, Ukraine International, VIM Airlines (Closed), Volotea, Xiamen.

Ortlieb Commuter Daypack High Visibility vs. Tom Bihn Synapse 25: which should you pack?

The Tom Bihn Synapse 25 carries 4L more than the Ortlieb Commuter Daypack High Visibility (21L vs. 25L), while the Tom Bihn Synapse 25 is the lighter pack at 0.8kg (vs. 0.86kg). For carry-on flexibility, the Ortlieb Commuter Daypack High Visibility fits 92% of the airlines we track — the higher of the two. If you prioritise packing volume, choose the Tom Bihn Synapse 25; if you want to travel lighter, the Tom Bihn Synapse 25 is the better call.