---
url: "https://onebag.travel/compare/4ur3vo1zzw/rei-co-op-ruckpack-18/ypfu4rph/tom-bihn-synapse-25/"
title: "REI Co-op Ruckpack 18 vs Tom Bihn Synapse 25"
description: "REI Co-op Ruckpack 18 vs Tom Bihn Synapse 25: capacity, weight, dimensions and how many airlines accept each as a carry-on, side by side."
source: "https://onebag.travel/compare/4ur3vo1zzw/rei-co-op-ruckpack-18/ypfu4rph/tom-bihn-synapse-25/"
---
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3.  REI Co-op Ruckpack 18 vs. Tom Bihn Synapse 25

# REI Co-op Ruckpack 18 vs. Tom Bihn Synapse 25

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

## [REI Co-op Ruckpack 18](https://onebag.travel/carryon/4ur3vo1zzw/rei-co-op-ruckpack-18/)

![Front facing view of the REI Co-op Ruckpack 18](https://res.cloudinary.com/obt/image/upload/c_fill,w_400/v1601601381/carryons/reirutpack_nq5156.webp)

<table class="table table-sm cmp-spec mt-2"><tbody><tr><td>Capacity</td><td>18 L</td></tr><tr><td>Weight</td><td>0.7 kg</td></tr><tr><td>Dimensions</td><td>44×26×18 cm</td></tr><tr><td>Airline fit</td><td>96%</td></tr><tr><td>Price</td><td>$65</td></tr></tbody></table>

## Feature by feature

| REI Co-op Ruckpack 18 | Feature | Tom Bihn Synapse 25 |
| --- | --- | --- |
| Storage |
|  | Compression | N |
| None | Expanded Capacity | None |
| 0 | Opening | 0 |
| side | Passport | front |
| N | Passthrough | N |
| Carry |
|  | Backpack | Y |
| removable | Hip Belt | removable |
| removable | Sternum Strap | removable |
| Inside |
| 15in | Laptop | 15in |
| 2 | Main Compartments | 6 |
| Y | Organizer | Y |
| Outside |
| × | Hard Shell | × |
| N | Rain-fly | N |
|  | Water Bottle Holder | 1, front |
| Y | Water Resistant | Y |

<table class="cmp-material"><tbody><tr><td colspan="2">Material</td></tr><tr><td>210-denier nylon ripstop</td><td>200 denier Halcyon/nylon ripstop fabric lining 400 denier nylon lower back</td></tr></tbody></table>

## [Tom Bihn Synapse 25](https://onebag.travel/carryon/ypfu4rph/tom-bihn-synapse-25/)

by [Tom Bihn](https://onebag.travel/carryons/?brands=Tom Bihn)

![Front facing view of the Tom Bihn Synapse 25](https://res.cloudinary.com/obt/image/upload/c_fill,w_400/carryons/fd7axrvmuogdgtfc9fwr)

<table class="table table-sm cmp-spec mt-2"><tbody><tr><td>Capacity</td><td>25 L</td></tr><tr><td>Weight</td><td>0.8 kg</td></tr><tr><td>Dimensions</td><td>51×34×23 cm</td></tr><tr><td>Airline fit</td><td>71%</td></tr><tr><td>Price</td><td>$250</td></tr></tbody></table>

## Key differences between the REI Co-op Ruckpack 18 and Tom Bihn Synapse 25

-   **Passport pocket:** Side on the REI Co-op Ruckpack 18; Front on the Tom Bihn Synapse 25.
-   **Main compartments:** 2 on the REI Co-op Ruckpack 18; 6 on the Tom Bihn Synapse 25.

Both have: 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. 47 accept only the REI Co-op Ruckpack 18, and 0 accept only the Tom Bihn Synapse 25.

### Only the REI Co-op Ruckpack 18 fits

Air Baltic, Air China, Air Malta, Air Niugini, Air Serbia, Air Seychelles, Air Tahiti, American Eagle, Asiana Airlines, ATA Airlines, Belavia, Blue Air, Bulgaria Air, China Eastern, easyJet, Emirates Airlines, Enter Air, Etihad Airways, flybe, Great Lakes Airlines, Gulf Air, Icelandair, InselAir, Juneyao Airlines, Liat Airlines, Luxair, Meridiana Fly, Nordwind Airlines, Pakistan International, Qatar Airways, Ravn Alaska, Regional Express, 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), Virgin Australia, Volotea, Xiamen.

## REI Co-op Ruckpack 18 vs. Tom Bihn Synapse 25: which should you pack?

The **Tom Bihn Synapse 25** carries 7L more than the **REI Co-op Ruckpack 18** (18L vs. 25L), while the **REI Co-op Ruckpack 18** is the lighter pack at 0.7kg (vs. 0.8kg). For carry-on flexibility, the **REI Co-op Ruckpack 18** fits 96% 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 REI Co-op Ruckpack 18 is the better call.