MaterialScopeHow much concrete for a 10 × 10 slab?
Compare thicknesses, extra material and bag quantities for a 10-foot-square slab.
Thickness changes the order
These figures assume straight-sided, level forms and a uniform thickness across 100 square feet. The table compares quantities only; it does not select a structurally suitable thickness.
| Thickness | Net concrete | With 10% extra | 80-lb bags* |
|---|---|---|---|
| 4 in | 1.23 yd³ | 1.36 yd³ | 62 bags |
| 5 in | 1.54 yd³ | 1.70 yd³ | 77 bags |
| 6 in | 1.85 yd³ | 2.04 yd³ | 92 bags |
*Bag counts assume 0.60 ft³ per bag and include the same 10% allowance. Ready-mix and bags are alternative purchase methods.
Work through the dimensions
10 × 10 × (4 ÷ 12) = 33.33 cubic feet. Divide by 27 to get cubic yards. Multiply the unrounded volume by 1.10 to add the allowance. Round only at the end, and confirm the supplier’s order increments.
Plan the job around the delivery
A small slab may still involve many bags. At 4 inches and 10% extra, the example needs 62 of the assumed 80-lb bags. Consider mixing capacity, handling and working time, then ask a ready-mix supplier about its minimum delivery and short-load charges.
Compare bag handling with a delivery
The 4-inch example rounds to 62 bags at 80 lb each: 4,960 lb of dry product in total. That is a handling quantity, not a vehicle payload recommendation. Arrange delivery or several suitable loads according to the vehicle rating, and keep bags dry until use. Confirm the mix yield on the label before buying.
Make a useful quote request
Give the supplier the 10 × 10-foot dimensions, specified thickness and 1.36 yd³ allowance-adjusted estimate. Ask about the smallest order, delivery charge and any short-load fee. For bags, compare the total price of 62 bags plus equipment and delivery with the ready-mix quote; price per bag alone does not capture the whole purchase.
Check the base before the pour
An uneven excavation can consume more material than the nominal dimensions suggest. Measure several depths and confirm that the base and forms match the design. Do not use this table to choose load-bearing capacity, reinforcement or local code requirements.
Use the bag calculator to change product yield, or the cost calculator to enter a supplier quote. Compare the 4-inch and 6-inch quantities before discussing the design with your project professional.
Product reference: QUIKRETE concrete mix technical data. Confirm the current label for your chosen product.
Change the measurements and allowance to match your plan.
Open Concrete Slab CalculatorMaterialScope editorial · Updated September 29, 2026 · Calculation methodology