Calculate concrete volume for cylindrical piers or tube forms, with an optional separate base. Enter the dimensions already selected for the project; the calculator reports each component and a combined material quantity without designing the support.
Measure the pier and base separately
For a round pier shaft, enter its actual diameter, height, and number of identical piers. The default model treats the shaft as a solid cylinder. When a wider base is part of the concrete, add that base as a second shape and identify whether it is circular or rectangular. Measure the pier height from the top face of the base so the shaft and base volumes meet without overlapping.
The distinction matters even when two pieces are poured together. If you enter shaft height from the bottom of the base and also add a full base thickness, the shared section is counted twice. A base may be wider, shallower, or shaped differently from the pier above it. Enter its own dimensions and quantity, and check the displayed component breakdown before accepting the total.
Volume formula and allowance
A cylindrical shaft uses V = π × (diameter ÷ 2)² × height. A round base uses the same circle-area relationship multiplied by its thickness. A rectangular base uses length × width × thickness. Calculate each non-overlapping component, multiply by its count, add the net volumes, and divide cubic feet by 27 for cubic yards. The order volume applies the selected allowance once to that combined net quantity.
The default concrete allowance is 10%, adjustable in the calculator. It is a planning choice, not a rule for pier construction. The result should keep net volume and order volume separate, then show a bag equivalent only when a named product is selected. Rounding each tiny component to a whole cubic yard before adding can exaggerate the total; preserve precision, sum the components, apply allowance, and round bags only at the final product conversion.
Worked example: four piers with round bases
Suppose there are four piers, each 1 ft in diameter and 3 ft high above a round base. Each shaft contains π × 0.5² × 3 = about 2.356 ft³; four shafts total 9.425 ft³. Give each base a 2 ft diameter and 0.5 ft thickness. Each base contains π × 1² × 0.5 = about 1.571 ft³, so all four bases total 6.283 ft³.
The combined net volume is about 15.708 ft³, or 0.58178 yd³. With 10% allowance, the order amount is about 17.279 ft³, or 0.63995 yd³. Using QUIKRETE Concrete Mix No. 1101 at approximately 0.60 ft³ per 80 lb bag gives 29 bags. That count is based on the product’s listed approximate yield; it does not include a separate footing, column, or other concrete that is not in the entered geometry.
Round and rectangular bases
A round pier can sit on either a round or a rectangular base in the supported quantity path. Use the actual plan dimensions of the base, not a dimension inferred from the tube. For a rectangular base, the volume is straightforward even when it is wider than the shaft. For an unusual sloped or stepped base, break it into simple shapes with clear, non-overlapping boundaries or use a known volume from project documents.
If a manufacturer supplies the inside diameter of a form, use the concrete diameter rather than the outside dimension of the form wall. A product sheet such as the Sonotube builders tube information can help identify form sizes, but the form must match what will be installed. An over-excavated, belled, or irregular hole is not represented by a uniform cylinder unless those extra regions are measured separately.
Pier quantity versus other concrete elements
This page is focused on pier shafts and optional bases as measured volumes. If the project also includes independent strip footings, rectangular pads, above-grade columns, or post holes, calculate those components with their own geometry and combine only after checking for overlap. Project terminology varies, so follow the drawings’ labels and dimensions rather than inferring a structural classification from a generic word such as pier or column.
A concrete volume is not a support design. The tool does not decide a pier diameter, depth, spacing, bearing capacity, reinforcement, connection, frost protection, or suitability for a particular building or deck. The AWC deck guide is a reference for deck planning, and the dedicated deck-footing page provides a separate bearing-area arithmetic path when the correct inputs are known. Neither replaces site-specific plans or local review.
Before you order
Check that the base and shaft share one boundary, the shaft height starts at the base top, the quantity is correct, and the selected diameter is the inside concrete dimension. Confirm the total in cubic yards and whether the 10% allowance is included. If ordering bags, match the exact package size and product yield; if ordering ready-mix, ask about minimum volume, partial loads, truck access, and scheduling.
The estimate covers only the shapes entered. It does not add excavation, forms, reinforcement, grade beams, cap blocks, or adjacent structural pieces automatically. If those belong to the concrete placement, include their measured volumes separately. For a broader foundation estimate, use the foundation cost page’s project-type range or its detailed material path, keeping an installed-budget result separate from the pier material subtotal.
Frequently asked questions
Does pier height include the base?
Enter pier height from the top of the base. The base is a separate shape, so this boundary avoids counting its volume twice.
Can I add a rectangular base to a round pier?
Yes. Enter the pier cylinder and the rectangular base as separate, non-overlapping components.
How many bags are needed for four piers with bases?
The example totals 15.708 ft³ net. At 10% allowance and about 0.60 ft³ per 80 lb QUIKRETE Concrete Mix No. 1101 bag, it rounds to 29 bags.
Should I use the outside diameter of the tube?
Use the inside diameter that defines the concrete. The form wall outside dimension is not the filled concrete diameter.
Does this calculator determine pier depth or capacity?
No. It estimates material for entered dimensions and does not evaluate soil, depth, loads, reinforcement, or support design.
Can I include a separate footing?
Yes, if you know its dimensions and enter it as another component. Check shared faces and do not count the same concrete in multiple shapes.