Jars, cans & cups
Volume of a Jar
Everyday round containers — jars, cans, cups and moulds. Enter the inside dimensions for a capacity in millilitres or cups.
This volume of a jar turns a round container's inside diameter and height into a capacity you can use in the kitchen or pantry, in millilitres and cups.
Kitchen and pantry volumes come down to the inside of the container, not the outside, and to remembering that nothing is filled to the very brim. With those two things in mind, a round tin's capacity is a two-second calculation.
The formula behind it
The volume of a cylinder is:
V = π r² hA worked example
Worked example. Take a cylinder with a diameter of 15 cm (so a radius of 7.5 cm) and a height of 30 cm. The base area is π × 7.5² = 176.71 cm², and multiplying by the height gives a volume of about 5.30 litres (5,301 cm³ · 1.40 US gallons).
Measure the inside of the container, not the outside — and remember most jars and cans are filled to just below the rim, so usable capacity is a touch less.
Conversions use standard factors: 1 US gallon = 231 in³, 1 Imperial gallon = 4.54609 L, 1 litre = 1000 cm³.
Using the calculator
- Measure across the circular end — the diameter or radius.
- If you measured the diameter, halve it to get the radius r.
- Square the radius and multiply by π to get the base area.
- Multiply the base area by the height h: V = π r² h.
- Convert the result into your preferred unit above.
Getting an accurate measurement
If you can only reach the top, measure the diameter across the opening and halve it. Keep every measurement in the same system, and let the tool convert between units for you.
After you have your answer
The figure above is usually the start, not the finish. These are the questions that tend to come next, answered here so you do not have to run another search:
What if the container is tapered rather than straight?
This assumes straight sides. For a gently tapered tin the straight-side figure is a close estimate; for a strong taper, measure at the average width for a better result.
How many cups or fluid ounces is that?
The millilitre result is shown next to cups and US fluid ounces, so a jar or tin capacity drops straight into a recipe.
How do I compare two tins?
Work out the volume of each tin and keep the batter depth similar. If the new tin holds less, reduce the mix or expect a taller bake.
Should I measure inside or outside?
Inside — the wall holds nothing. Most containers are also filled to just below the rim, so usable capacity is a touch less than the geometric figure.
What to watch out for
Two things trip people up: squaring the wrong number, and forgetting that the answer is cubic. If a result looks four times too big or too small, you have probably swapped radius and diameter somewhere, so it is always worth re-reading the measurement you are least sure of. It also helps to glance at the equivalent units; if the litre and gallon figures are both off by the same factor, the input is the culprit, not the maths.
One result, every unit
Showing every unit at once is about speed and safety: you see the answer in litres, gallons and cubic feet side by side, so there is no chance of applying the wrong conversion factor. Change the output unit at the top to make any of them the headline figure, switch the precision to exact if you want the value in terms of pi, and use copy-result to paste a tidy summary wherever you need it.
Keep going
Once you have your answer you may also want to work in litres & liters cylinder volume gallons. These related calculators pick up where this one leaves off:
When this comes in handy
It comes in handy across quite different tasks:
- Swapping between two baking-tin sizes
- Measuring a jar's true capacity
- Portioning storage containers
To sum up, the whole job is two measurements and one formula. Enter them above, pick your unit, and you have an accurate figure plus every equivalent unit beside it. Keep a copy with the copy-result button, save the shareable link if someone else needs the same numbers, and use the history panel to compare a few options without starting from scratch.
Frequently asked questions
How do I find the volume of a jar or can?
How do I swap between two round baking tins?
What is the formula for the volume of a cylinder?
V = π r² h — the area of the circular base (π r²) multiplied by the height (h). If you have the diameter instead of the radius, halve it first: r = d ÷ 2.