For most paddlers, a 2 liter dry bag holds the essentials: phone, keys, wallet, a snack. A 10 liter adds a warm layer, water, and lunch for a full day out. A 20 liter carries an overnight kit and wears as a backpack. Match the bag to the day, not the other way around.
The sizing charts you find online list liters and stop there, which is not much help when you are standing at a launch trying to figure out if your stuff will fit. Liters are an abstraction. A day on the water is not. Here is what each size actually holds once it is packed and rolled shut.
How big is a 2L, 10L, or 20L dry bag in real terms?
A 2 liter is the phone-and-keys bag. Phone, car key, a card and some cash, lip balm, a bar. It clips to a deck line or a PFD and stays out of your way. This is the one that lives in your boat whether or not you planned a real trip.
A 10 liter is the day bag. On top of the essentials, it takes a warm layer, a water bottle, lunch, and a small first aid kit, with room to roll the top down. It comes with a single removable shoulder strap, so you can carry it from the car to the water without juggling.
A 20 liter is the overnight. A full change of clothes, camp layers, and the soft gear you want to stay dry through a night out. It wears as a backpack with two removable straps, which matters on the walk in when your hands are already full of boat and paddle.
What size dry bag for paddleboarding or a kayak day trip?
For a morning on a paddleboard or a half day in a kayak, a 2 liter clipped where you can see it covers what you actually need to protect. If you like to carry a layer, water, and real food, size up to a 10 liter and lash it to the deck. The honest answer is that most day paddlers are best served by owning both: the small one that never leaves the boat, and the day bag for when the trip gets longer. For the full decision, see our guide on how to choose a dry bag.
What size for camping, an overnight, or the whole family?
Once you are packing for a night out or for more than one person, think in several bags rather than one big one. A 20 liter as your main soft-gear bag, a 10 liter for the layer-and-lunch kit you want to reach on the water, and a 2 liter for the phone. Multiple sized bags pack tighter in a hull than one large sack and let you find things without unpacking everything. That approach is its own small skill, which we cover in how to pack your dry bags for a camping trip.
A note on sizing up
A roll-top needs the top rolled down at least three times and clipped to keep water out, and that eats a little space. So if you are between sizes, size up. A slightly empty bag rolls and seals fine. A stuffed one you cannot roll does not. For the full method, see how to seal a dry bag.
Find your size
Wild Currents makes roll-top dry bags in 2 liter, 10 liter, and 20 liter, in prints worth carrying. Browse the collection and pick the size that matches your water.
Frequently Asked Questions
What is the most useful dry bag size for paddling?
For most people it is a 10 liter. It carries a full day of essentials plus a layer and lunch, comes with a shoulder strap, and still packs down when it is light. If you only own one, own the 10.
Is a 2 liter dry bag big enough for a phone and keys?
Yes. A 2 liter comfortably holds a phone, keys, a card, and a small snack, with room to roll the top for a proper seal. It is designed to clip to a deck line or PFD and stay close.
What size dry bag do I need for an overnight kayak or canoe trip?
A 20 liter as your main bag for clothes and soft camp gear, ideally paired with a 10 liter for the day layer and a 2 liter for the phone. Several sized bags pack better in a hull than one oversized sack.
Should I size up or size down when I am unsure?
Size up. A roll-top needs the top rolled at least three times to seal, so a little extra room helps. An overstuffed bag you cannot roll will not keep water out.
Can I use one big dry bag instead of several small ones?
You can, but several sized bags are easier to pack tightly, easier to balance in a boat, and far easier to search when you want one thing. Most paddlers end up with a small, a medium, and a large.