How Much Concrete for a 10×10 Slab?
10 × 10 ft at 4-inch depth, with a 10% ordering allowance.
4-inch slab estimate
Includes 10% overage.
Base volume: 1.23 yd³
With 10% overage: 1.358 yd³Confirm your supplier’s ordering increment. Bag counts below include the same overage.
Need a different size or thickness? Use the full calculator to get an estimate.
Calculate another sizeCompare delivery for 1.358 yd³ with transporting and mixing 62 × 80 lb bags. Ask about minimum orders, access and delivery fees.
10 × 10 ft slab: thickness comparison
Same 100 ft² footprint, with 10% overage. Depths illustrate quantities, not structural recommendations. Bag yield: 0.60 ft³ per 80 lb bag.
| Thickness | Base yd³ | With overage yd³ | 80 lb bags |
|---|---|---|---|
| 4 in | 1.235 | 1.358 | 62 |
| 5 in | 1.543 | 1.698 | 77 |
| 6 in | 1.852 | 2.037 | 92 |
| 8 in | 2.469 | 2.716 | 123 |
The 4-inch example needs 62 eighty-pound bags: 4,960 lb of dry mix. Plan transport and mixing equipment, and compare delivery options.
Calculation method
The formula is: Volume = Length × Width × Thickness. Convert thickness from inches to feet first, then divide by 27 to get cubic yards.
- Step 1; Volume 10 × 10 × (4 ÷ 12) ft = 33.33 cu ft
- Step 2; Cubic Yards 33.33 ÷ 27 = 1.23 cu yd
- Step 3; Add 10% Waste 33.33 × 1.10 = 36.67 cu ft
- Step 4; 60 lb Bags 36.67 ÷ 0.45 = ~82 bags
- Step 5; 80 lb Bags 36.67 ÷ 0.60 = ~62 bags
Practical Tips for a 10×10 Slab
- Use the specified thickness. The 4-inch figure here is a quantity example, not a structural recommendation.
- Allow for overage. 10% is a starting allowance, not a universal specification. Allow for uneven ground and spillage.
- Compact your sub-base first. 4–6 inches of gravel under the slab prevents settling and cracking.
- Don't thin the mix with extra water. It makes mixing easier but weakens the concrete significantly.
- Cure for at least 7 days. Keep the slab moist after pouring. This dramatically increases final strength.
- Round up, not down. You cannot pour half a slab and come back; you'll get a visible cold joint.
Assumptions
QUIKRETE Concrete Mix technical data provides the 0.45 ft³ and 0.60 ft³ bag yields used here. Other mixes can have different yields.
- ◦ Slab dimensions: 10 ft × 10 ft at 4 inches thick. Changing thickness changes all totals.
- ◦ Concrete yield: 60 lb bags = 0.45 cu ft; 80 lb bags = 0.60 cu ft. Standard manufacturer figures.
- ◦ Waste factor: 10% applied. Increase to 15% for rough terrain or irregular shapes.
- ◦ Results are estimates only: Confirm quantities with your concrete supplier before ordering.