How many fuel canisters

How many fuel canister do I need for a 4 day/ 3 night hike? Needed for myself and one other person. I'm planning to at least eat every morning and night with a light snack in the afternoon.

One small canister should be enough, but if your at all worried get one large canister. Or have your friend carry a back up canister.

this might be something to consider asking your stove's manufacturer about.

Are you planning on heating anything during that afternoon snack?
Boil-in bag meals or actual cooking (EX noodle dishes and the like.)?
What size fuel canisters do you buy?
What is your altitude?

I plan to use one ounce of fuel per day and usually don't burn all of it. I am usually solo and am a boil water and soak type of cook. All my meals are pre packaged and will rehydrate in boiled water in a freezer bag (actually a Ziplock storage bowl) in an insulated bag. Here is how I cook: breakfast, boil 1.5 cups for coffee and 1 cup for cocoa; lunch, no cooking but will sometimes brew a cup of tea; dinner, boil 1 cup for soup, 1.5-2 cups for main meal and 1 cup for herb tea. As I noted it averages out to a little less than an ounce per day. Most of my hiking is in western mountains and seldom below 6500' elevation.

One large (8 oz.) canister ought to do it with fuel to spare, but there are a lot of important factors you leave out of your question.

Fuel use is not affected by how much or how often you eat, but by how often and how much you use your stove. For example, I eat a breakfast, divide my lunch into two smaller meals, and eat a supper, but I only use the stove once a day to cook my supper. The other meals don't require me to fire up the stove. Also, I don't heat water for hot drinks like coffee or tea, except on my rare trips when it is cold weather. That right there drops out a lot of stove use.

How you go about preparing your hot meals also factors in. Some people use the stove to bring water to a boil, then quickly combine their food with that boiling water and place it into a 'cozy' that retains the heat at near the boiling point for quite a while. So, as soon as the water boils they are finished with their stove and can turn it off. Others keep the stove lit and simmer their food until it is ready. Still others like to get elaborate with their meals, with several courses, steps and stages of cooking.

Finally, I use a windscreen, which improves the efficiency of my stove, because none of the heat is blown away from my cooking pot.

All this sort of thing is what we don't know about how you plan to use your stove, so we're somewhat shooting in the dark here.

For myself alone, I tend to have my stove lit for about 15 minutes a day, but never at the highest blast, and I use about a third of an ounce of fuel per day, so that a small (4 oz.) canister will last me more than ten days.

Thanks for the quick reply.
I'm planning on just boiling enough water to fill dehydrated food bags. So maybe 16 oz of water at a time. I'm unsure of the altitude will be using at the Red river Gorge area in Kentucky.
I will look more in to the larger canisters.

Thanks again for the quick reply.

Try testing on your back patio, starting with cold water (chilled in your refrigerator). Weigh the canister before and after to determine how much fuel is used. That way you know how much fuel is needed for your specific style of cooking. Do this several different times and calculate the average, adding enough for one or two additional meals for "fudge factor." If it's cool outside with a wind, so much the better--more realistic conditions!

You should be testing your meals before you go out, anyway. Nothing more horrible than getting out and discovering that the dinner you had planned as a special treat turns out to be inedible! (Been there, done that! )

For me, a 3-night/4-day trip is at the dividing line between the small and medium canister. What a lot of people here call "large" is really the medium canister. The "large" has the same amount of fuel as two medium canisters. I use a small for 1-3 nights, medium for a 4-7 nights, and large for 10-12 days. For that odd 8-9 day trip I take one small and one medium. I also really cook, not just boil water and like several hot drinks when nights are cold.

I would take the medium at first. After you have backpacked enough to know your needs, you may be able to size down to the small. I seldom use the small canisters because they cost nearly as much as a medium and it is really nice to have extra fuel for more hot drinks or even to warm water to wash my face! The Jet-boil system uses a heat exchanger and if you have this type of system, a small canister should do fine. However, the added weight of the heat exchanger pot just about evens it out in total weight. Experienced backpackers are able to squeeze more cooking out of the small canister, but as a beginner, you may not be as efficient.

Where do you find the large? I've never seen them! I'd sure like to have them for long trips instead of taking two medium or a small and a medium! The amount of metal container per the amount of fuel would be a lot less!

On a long trip, where you won't be passing resupply points, would the "backup" value of two smaller canisters instead of one larger canister justify the extra 2 or 3 ounces? When I'm planning to spend a week at Isle Royale, where I'll be walking away from the only store and won't swing back by it until the end of the trip, I take 2 small canisters instead of a medium. My thinking is that, if I mess up the threads or jam the valve on one canister, I can still get at half my fuel.

small(jetboil) = 3.53 oz. gas, 9 oz total weight
medium (jetboil) = 8.11 oz gas, 13 oz total
large (jetboil) = 16 oz gas, 22.7 oz total

each brand may vary slightly.

two smalls (18 oz total) < one medium (12 oz total) 6 oz savings
two mediums (26 oz total) = one large (22.7 oz total) 3.3 oz savings

So, the medium is quite a savings over two smalls. The large is not much difference, although two mediums cost more than one large.

I get the large cans at our REI here. Currently they only carry the Jetboil brand. Several outdoor stores in Wyoming also carry the large canisters. I have never seen a large canister at Walmart, Big5 or other regular outdoor stores.

The only time I mis-threaded a canister, it blew up the entire stove, so having an extra canister would have not made any difference. I a have never had a "dud". Every canister I have purchased has worked fine. It is more likely the stove will malfunction.

I've never had a dud, either. My only exploding stove was an MSR Whisperlite gasoline stove. But the Portland area REI stores don't carry the 16 oz canisters, or at least not any time i've been there (admittedly, I don't go very often). Bummer! Next time I go to Wyoming (probably the only place I'll do a ten-dayer) I'll check the Great Outdoors Shop in Pinedale. Or get a recommendation from you for Lander if I go to the east side.

Those containers do weigh something, and, as I mentioned, the larger the container, the less the weight of the container compared to the weight of the fuel it contains. Plus the valves are the same size for each.

I have only seen the big canisters at REI as well. Jetboil brand.