Is a soda maker worth it? Sparkling water cost per litre

How the cost per litre is worked out

A soda maker turns tap water into sparkling water with CO₂ from a refillable cylinder, so the running cost is mostly gas, plus any flavour you add. The calculator splits it into three prices per litre:

• Gas: the refill price divided by the litres one cylinder makes. $16.99 ÷ 60 litres is about $0.28 a litre.
• Flavour: the price of a bottle of syrup or drops divided by the litres it flavours in your own use.
• Bottled: the shelf price divided by the bottle size, so a $1.25 one-litre bottle is $1.25 a litre and a $0.99 half-litre is $1.98.

The weekly saving is the difference times the litres you drink. The machine pays for itself when the savings add up to its price: break-even weeks = machine price ÷ (bottled cost − home cost) per week The card turns that into a date counted from today, and shows the spend of both habits over time.

The litres per cylinder is a claim, not a constant

SodaStream's US site says its 60 L cylinders "will on average make up to 60 liters of sparkling water", and adds that there is no one-size-fits-all answer because it depends on the level of carbonation you use. On 5 November 2026 the same site listed a cylinder exchange at $16.99, marked as a special price, and a spare cylinder bought outright at $31.99. Prices change, and other makers and countries differ, so the calculator takes whatever you enter.

Physics explains why the count varies. Water carbonated to 3.5 volumes holds about 6.9 g of CO₂ per litre, and the gas left in the bottle's headspace is let out when you release it. The fizzier you like it, the more you use per litre. The best number is your own: write the date on a new cylinder and count the bottles until it runs dry.

Plastic bottles not bought

The bottle count is the litres you would otherwise buy divided by the bottle size. At 7 litres a week in one-litre bottles that is about 365 bottles a year; in half-litre bottles, about 730. The machine's own bottles and the cylinders are reused, which is the point of the comparison.

Worked examples

• A litre a day, plain: 7 litres a week at $0.28 against $1.25 saves about $6.77 a week, so a $100 machine pays for itself after 14.8 weeks. In a year that is about 6 cylinders and 365 bottles not bought.
• With flavour: add a $6 bottle of flavouring that does 9 litres in your glass, and home-made costs $0.95 a litre. The saving falls to $2.10 a week and break-even moves to about 48 weeks.
• Cheap store-brand bottles: at $0.50 a litre bottled, plain home-made saves $1.52 a week at 7 litres, and the $100 machine takes about 66 weeks to pay off.

So is a soda maker worth it?

On cost alone, it depends on three things: how much sparkling water you drink, what you pay for it now, and how much flavour you add. Heavy drinkers of branded sparkling water break even within months; light drinkers of cheap own-brand bottles may take more than a year, or never, especially with flavouring. Cost is not everything, either: there are no crates of bottles to carry home and fewer to recycle. If you add syrups, the soda syrup calculator shows the sugar in each glass, and the carbonation calculator explains why colder water takes the fizz better.

Common mistakes

• Comparing with the single-bottle price when you usually buy multipacks; use the price you actually pay per bottle.
• Taking the claimed litres as a promise. It says "up to"; fizzier water means fewer litres.
• Using the spare-cylinder price for refills. Buying an extra cylinder outright costs more than exchanging an empty one.
• Forgetting flavour. Drops and syrups can cost more per litre than the gas.