At 4 inches thick, a 10×10 slab has a theoretical volume of about 1.23 cubic yards. With a 10% waste allowance, the planning quantity is about 1.36 cubic yards.
Thickness is the key variable
The same 100-square-foot slab uses more concrete as thickness increases. Choose thickness based on use, soil, base, reinforcement and local requirements rather than quantity alone.
Use actual form dimensions
Enter length, width and thickness in the Concrete Calculator. Small differences in forms or subgrade can affect the final order.
Compare ready-mix and bags
For a pour this size, compare supplier delivery fees and short-load charges against the labor of mixing many bags.
Verify before ordering
Supplier increments and site conditions can change the practical quantity. Confirm the final order with the supplier or contractor.
Run your own numbers: Use the Concrete Calculator with your exact thickness.