Formula
Cylinder volume = π × radius² × height. If diameter is entered, radius = diameter ÷ 2. Litres = cubic metres × 1,000. Optional planning volume = measured volume × (1 + allowance percent ÷ 100).
Measurement & Geometry
Cylinder Volume Calculator
Calculate cylinder volume from radius or diameter and height, with litres, cubic metres, cubic feet and optional allowance shown for tanks, tubes, posts and classroom work.
Measurement & Geometry
Cylinder Volume Calculator
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Live resultReadyCalculator queued
Formula used
Cylinder volume = π × radius² × height. If diameter is entered, radius = diameter ÷ 2. Litres = cubic metres × 1,000. Optional planning volume = measured volume × (1 + allowance percent ÷ 100).
This is the method behind the answer, so the result can be checked rather than simply trusted.Visual grid
This result measures part of the space you live in
Length, area, volume and material estimates are grid problems too: measure the space, account for edges and allowances, then turn the pattern into a number you can use.
Micro-timehours, minutes, shiftsHuman scaledays, weeks, projectsMacro-timemonths, years, calendars
Measured outputReady
Space calculations turn a real surface, room, run or volume into cells, edges and allowances that can be quoted, ordered or checked.
CalculationTime
Cylinder Volume Calculation Report
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Inputs
- Diameter
- 1.2 metres
- Radius override
- 0 metres
- Height / length
- 2 metres
- Allowance
- 5 percent
Method
Cylinder volume = π × radius² × height. If diameter is entered, radius = diameter ÷ 2. Litres = cubic metres × 1,000. Optional planning volume = measured volume × (1 + allowance percent ÷ 100).
- Diameter 1.2 m gives radius 0.6 m. Volume = π × 0.6² × 2 = 2.2619 m³. That is 2,261.9 litres. With a 5% allowance, the planning volume is 2.3749 m³, or about 2,374.9 litres.
Assumptions
- The cylinder is treated as a straight circular cylinder with flat circular ends.
- Radius and height must use the same length unit; the default inputs use metres.
- The allowance is shown as planning volume only and is not part of the exact geometric cylinder.
- Horizontal tanks, domed ends, sloped cylinders, wall thickness and partial fill levels need specialist tank geometry or manufacturer data.
Notes
Use this space on the printed report for client, supplier, classroom, job-location, measurement, quote or approval notes.
Worked example
Diameter 1.2 m gives radius 0.6 m. Volume = π × 0.6² × 2 = 2.2619 m³. That is 2,261.9 litres. With a 5% allowance, the planning volume is 2.3749 m³, or about 2,374.9 litres.
Professional note
Master’s Tip: measure the internal diameter when you need capacity. External diameter is useful for clearance and fabrication, but wall thickness can make the real internal volume noticeably smaller.
Regional and unit assumptions
Standard or basis: Euclidean cylinder geometry using SI metre and litre display. One cubic metre equals 1,000 litres; cubic feet are shown as a secondary comparison using the international foot relationship.
Assumptions and limitations
- The cylinder is treated as a straight circular cylinder with flat circular ends.
- Radius and height must use the same length unit; the default inputs use metres.
- The allowance is shown as planning volume only and is not part of the exact geometric cylinder.
- Horizontal tanks, domed ends, sloped cylinders, wall thickness and partial fill levels need specialist tank geometry or manufacturer data.
Methodology & Accuracy
How this calculator is checked
CalculationTime pages are built around visible arithmetic: the formula, assumptions, worked example and practical limitations are shown so the result can be checked rather than simply trusted.
Formula used
Cylinder volume = π × radius² × height. If diameter is entered, radius = diameter ÷ 2. Litres = cubic metres × 1,000. Optional planning volume = measured volume × (1 + allowance percent ÷ 100).
Standard or basis
Standard or basis: Euclidean cylinder geometry using SI metre and litre display. One cubic metre equals 1,000 litres; cubic feet are shown as a secondary comparison using the international foot relationship.
Where a calculator follows a named legal, trade or industry standard, that standard is cited visibly. Otherwise the page uses transparent general arithmetic and states its limits.Master's Tip
Master’s Tip: measure the internal diameter when you need capacity. External diameter is useful for clearance and fabrication, but wall thickness can make the real internal volume noticeably smaller.
Related calculators
Questions
How do you calculate cylinder volume?
Square the radius, multiply by pi, then multiply by the height: volume = π × r² × h.
Can I use diameter instead of radius?
Yes. Enter the diameter and leave the radius override at zero. The calculator uses radius = diameter ÷ 2.
What unit is the result in?
The main result is cubic metres with litres shown beside it. Cubic feet are also shown as a secondary reference.
Is this suitable for a tank?
It works for a simple straight cylindrical tank when the full internal diameter and length are known. Domed ends, wall thickness and partial fill levels need a more specific tank calculation.
Why is the allowance separate?
The measured cylinder volume is geometry. Allowance is a planning assumption for headspace, waste or ordering margin, so it should not be mixed into the exact volume.
Calculation note
Cylinder volume is one of the most useful bridge formulas between classroom geometry and real measurement. It appears in tanks, pipes, drums, concrete cores, posts, silos, cans and tubes because many manufactured objects use circular cross-sections.
A cylinder is area carried through a length
The formula is easier to trust when it is read in two parts. First find the circular end area with π × radius². Then carry that same area through the height or length of the cylinder. That gives cubic units because a square-unit area is extended through a linear distance.
Diameter is often easier to measure than radius
On a real tank, pipe or tube, people usually measure straight across the opening. The calculator accepts diameter first because that matches tape-measure practice, then converts it to radius internally before applying the formula.
Capacity and outside size are not always the same
A pipe or tank can have a large outside diameter but a smaller internal capacity because of wall thickness, liners, domed ends, fittings or unusable headspace. The printable report keeps the dimensions, formula and allowance visible so those assumptions can be checked before ordering, filling or quoting.
Sources and further readingNIST: Guide for the Use of the International System of UnitsWolfram MathWorld: Cylinder