How Many Drinks Does a 5 Gallon Bag of Syrup Make?

A 5 gallon bag-in-box of soda syrup makes 30 gallons of finished soda at the standard 5 to 1 mix. That’s 3,840 ounces, or about 342 sixteen-ounce drinks with a normal 30% ice fill, and 240 if you pour to the rim with no ice.

The number most people quote is the no-ice number. It’s wrong for every restaurant that puts ice in the cup, which is all of them.

My favorite part of every bag-in-box is the half-perforated triangle that says “press with thumb.” It expects you to punch through two solid layers of cardboard with the power of one thumb. Once you get it open, here is what is actually inside.

The short answer, by box size #

Every number below assumes a 5 to 1 mix (5 parts water, 1 part syrup), which is what most colas and most fountain syrups run.

Box size	Syrup	Finished soda	16 oz drinks with 30% ice	16 oz drinks, no ice
5 gallon	640 oz	30 gallons (3,840 oz)	342	240
3 gallon	384 oz	18 gallons (2,304 oz)	205	144
2.5 gallon	320 oz	15 gallons (1,920 oz)	171	120

The 3 gallon math matches what WebstaurantStore lists on its 3 gallon Mountain Dew box: about 18 gallons of prepared soda, or 192 twelve-ounce servings with no ice (WebstaurantStore).

If you want to run your own box, cup and ice numbers, the fountain drink cost calculator does this math and shows every step.

How the math works #

Three steps. You can do it on a bar napkin.

1. Syrup in ounces. A gallon is 128 ounces. 5 gallons is 640 oz, 3 gallons is 384 oz, 2.5 gallons is 320 oz.
2. Times the mix. At 5 to 1, every ounce of syrup becomes 6 ounces of soda (5 water plus 1 syrup). 640 x 6 = 3,840 oz.
3. Divided by the soda in one cup. Not the cup size. The soda that actually goes in it after ice. A 16 oz cup with 30% ice holds 11.2 oz of soda. 3,840 / 11.2 = 342 drinks.

That third step is where people get it wrong. Ice takes up room, and room you fill with ice is room you don’t fill with syrup.

Drinks per box by cup size #

5 gallon box (3,840 oz of soda) #

Cup	With 30% ice	No ice
12 oz	457	320
16 oz	342	240
20 oz	274	192
24 oz	228	160
32 oz	171	120

3 gallon box (2,304 oz of soda) #

Cup	With 30% ice	No ice
12 oz	274	192
16 oz	205	144
20 oz	164	115
24 oz	137	96
32 oz	102	72

2.5 gallon box (1,920 oz of soda) #

Cup	With 30% ice	No ice
12 oz	228	160
16 oz	171	120
20 oz	137	96
24 oz	114	80
32 oz	85	60

Numbers are rounded down to whole drinks. Nobody sells 342.8 of anything.

What changes the count #

Ice fill. 30% is a normal dine-in fill. Drive-thru cups often run 40% or more. More ice means more drinks per box and a lower cost per drink. A 16 oz cup at 40% ice gets you 400 drinks from a 5 gallon box instead of 342.

Mix ratio. Diet sodas often run 4 to 1, and some specialty syrups run 6 to 1. At 4 to 1, a 5 gallon box makes 3,200 oz of soda, or about 285 sixteen-ounce drinks with ice. If your diet box runs out faster than your regular, that’s usually why.

Refills. Refills don’t change how many drinks a box makes. They change how many customers a box serves. At the common rule of thumb of 1.4 drinks per customer with free refills, 342 drinks covers about 244 customers.

A dispenser that’s out of calibration. If the valve is pouring 4 to 1 when it should pour 5 to 1, you’re using 20% more syrup on every drink. The box runs out early, and the soda tastes heavy. The distributor will calibrate it for free if you ask.

Why the count matters #

The drink count is how you get your cost per drink. Take what you paid for the box and divide by the drinks it makes.

A $90 box of branded cola that makes 342 drinks is about $0.26 of syrup per drink. Add the cup, lid, straw and a cent of CO2 and you’re near $0.45. On a $3.49 drink that’s a pour cost around 13% before refills.

That’s the cheap part of the cup. For the full breakdown, including what free refills really cost you, read how much a free refill actually costs.

Use the count to check your inventory #

If you know how many drinks a box should make, you can tell when it doesn’t.

Track boxes used against fountain drinks sold for a week. If a 5 gallon box should cover about 342 sixteen-ounce drinks and you’re only getting 250, something is off. Usually it’s one of these, in this order:

1. The mix ratio drifted.
2. The cup vendor changed the cup.
3. Somebody is pouring with no ice.
4. A leak in a syrup line.
5. Drinks going out that never hit the register.

The same check works for draft beer. The keg cost calculator does the pours-per-keg version.

Common questions #

How many gallons of soda does a 5 gallon bag-in-box make? 30 gallons at a 5 to 1 mix. 640 oz of syrup becomes 3,840 oz of soda.

How much soda does 2.5 gallons of syrup make? 15 gallons, or 1,920 oz. That’s about 171 sixteen-ounce drinks with 30% ice.

How many 12 oz drinks are in a 5 gallon box? About 457 with 30% ice and 320 with no ice.

Does a 3 gallon box make 3/5 of a 5 gallon box? Yes. 384 oz of syrup versus 640 oz, so about 60% of the drinks.

What’s the cost per drink from a bag-in-box? Box price divided by drinks per box, plus the cup, lid, straw and CO2. Plug yours into the fountain drink cost calculator.

Want this as a spreadsheet? #

The Bar and Fountain Cost Kit runs this math for every box and cup size you carry, plus draft beer, liquor and a weekly pour cost tracker. It costs $10 and works in Excel or Google Sheets.