Concrete Cylinder Calculator
Calculate concrete for identical cylindrical pours using diameter, height, quantity, waste allowance and bag yield.
Default project preview
0.86 yd³
Concrete bags
39
Volume per cylinder
5.3 ft³
Circumference
4.71 ft
Curved form area
56.5 ft²
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Input and output guide
What each value means
The labels and units below are part of this calculator’s visible methodology. Replace every default with measurements or product data from the actual project.
Cylinder diameter
Enter this project assumption in in. The current imperial default is 18 in.
Cylinder height
Enter this project assumption in ft. The current imperial default is 3 ft.
Number of cylinders
Enter this project assumption in a unitless value. The current imperial default is 4. Minimum: 1.
Extra allowance
Enter this project assumption in %. The current imperial default is 10 %. Minimum: 0. Maximum: 50.
Concrete yield per bag
Enter this project assumption in ft³. The current imperial default is 0.6 ft³.
Ready-mix price
Enter this project assumption in per yd³. The current imperial default is 165 per yd³. Minimum: 0.
Price per bag
Enter this project assumption in a unitless value. The current imperial default is 7. Minimum: 0.
How to read the outputs
Concrete bags
rounded full bags. Default preview: 39.
Volume per cylinder
before allowance. Default preview: 5.3 ft³.
Circumference
each cylinder. Default preview: 4.71 ft.
Curved form area
all cylinders. Default preview: 56.5 ft².
Placed weight
planning density. Default preview: 3,495 lb.
Cost comparison
ready-mix / bags. Default preview: $142.55 / $273.00.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Cylinder volume = π × radius² × height. Multiply by quantity, apply the allowance, then divide by bag yield and round up.
Reviewed project guidance
How to use this estimate in a real project
Last reviewed: July 30, 2026
Use this calculator to estimate concrete volume for one or more cylindrical forms, piers or test-sized shapes from diameter and height. It supports quantity planning and does not determine structural capacity or testing procedures.
Calculation steps
- 1Convert diameter to radius.
- 2Convert all dimensions to consistent units.
- 3Calculate one cylinder as π × radius² × height.
- 4Multiply by quantity, add allowance and convert to purchasing units.
Worked numerical example
A cylinder 24 in in diameter and 3 ft high has a radius of 1 ft, so volume is π × 1² × 3 = 9.425 ft³. Four cylinders require 37.7 ft³ before waste.
Purchasing and rounding
Ready-mix and bagged products are rounded using their actual sold increments and yield. Narrow forms may need extra allowance for placement loss.
Interpret the result
Diameter has a squared effect on volume, so small diameter changes are more significant than equal changes in height.
Page-specific assumptions
- True circular cross-section.
- Uniform diameter and height.
- Solid cylinder without a core.
- No reinforcement deduction.
Common mistakes
- Using diameter instead of radius in the formula.
- Failing to square the radius.
- Mixing inches and feet.
- Treating volume as structural capacity.
Primary and technical references
BuildMeter provides planning estimates, not engineering, architectural, electrical, mechanical, plumbing, permit or code approval. Review the methodology and verify final decisions with product documentation and qualified professionals.
BuildMeter Guides
Understand the measurements and assumptions
Use these visible reference guides before changing project inputs or planning allowances.
FAQ
Concrete Cylinder Calculator questions
Should the diameter be measured inside the form?+
Yes. Use the intended finished concrete diameter inside the cylindrical form.
Does this calculate hollow cylinders?+
No. It assumes each cylinder is completely filled with concrete.
Can this size a structural pier?+
No. Pier diameter, reinforcement and bearing capacity require project-specific engineering.