What this calculator does
Overrun is the air whipped into ice cream during churning, expressed as a percentage of the original mix volume. Four litres of mix that comes out as six litres of ice cream has 50% overrun.
It is the single biggest difference between cheap and premium ice cream. Commercial ice cream commonly runs 50 to 100% overrun, meaning up to half the tub is air. Premium products sit around 20 to 40%, which is why they feel dense and why a litre of one weighs so much more than a litre of another.
The formula
Overrun is the increase in volume divided by the original mix volume, expressed as a percentage. The yield multiplier is the final volume divided by the mix volume, which is the same information stated as a factor. Overrun can also be calculated from weights, by comparing the weight of equal volumes of mix and finished ice cream.
| Term | Meaning |
|---|---|
| Overrun | The percentage volume increase from air incorporated during churning. |
| Mix volume | The liquid volume before churning. |
| Yield multiplier | Final volume divided by mix volume, so 50% overrun is a multiplier of 1.5. |
| Legal minimum | Many jurisdictions set a minimum weight per volume for ice cream, which caps how much overrun is permitted. |
The inputs explained
| Field | What to enter |
|---|---|
| Base mix volume (L) | Volume of mix before churning. |
| Final churned volume (L) | Volume of finished ice cream after churning, in the same units. |
When to use it
Checking a churn is working properly
Overrun well below what a machine normally achieves points to a problem with the dasher, the mix temperature or the fill level.
Comparing homemade against commercial
Domestic machines typically achieve 20 to 30% overrun, which is why homemade ice cream is denser and also why it takes up less space than the mix volume suggests.
Costing a product
Overrun determines how much saleable volume a batch of mix yields, so it goes directly into the cost per litre.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
What overrun does each final volume give?
Four litres of mix churned to a range of finished volumes.
Questions
What is a typical overrun?
Commercial ice cream commonly runs 50 to 100%. Premium products sit around 20 to 40%, and gelato lower still at roughly 20 to 30%. Domestic machines usually achieve 20 to 30% because they churn more slowly and incorporate air less efficiently.
Is high overrun bad?
Not inherently, but it is what lets a producer sell air. Some overrun is necessary for a scoopable texture, since a completely airless frozen mix is hard and icy. Very high overrun produces a light, fast-melting product and, importantly, less of anything else per litre.
How do I measure overrun at home?
Weigh the same container full of mix and then full of finished ice cream. Overrun is the mix weight divided by the ice cream weight, minus one, times 100. Weighing is more reliable than trying to measure the volume of a soft frozen product.
Why is ice cream sold by volume rather than weight?
Convention, largely, and it is why overrun matters commercially: two tubs of the same volume can differ substantially in how much ice cream they contain. Many jurisdictions set a minimum weight per unit volume precisely to limit how far this can be pushed.
For chilling drinks rather than freezing, see the drink chilling calculator. For converting ingredient volumes to weight, see the cups to grams calculator.