How much concrete for a 15×30 slab 5 inches thick?
Answer
6.94 cubic yards
261 bags of 80lb concrete mix417 bags of 60lb mixOrder ready-mix delivery (~$1,041)Add 10% for waste = 7.63 cy
Need a custom calculation?
Open the full calculator with custom inputs
How We Calculated This
Cubic yards = (L × W × D/12) / 27
(30 × 15 × 5/12) / 27 = 187.50 / 27 = 6.94 cubic yards
Related Calculations
How much concrete for a 4×4 slab 4 inches thick?0.20 cubic yardsHow much concrete for a 4×4 slab 5 inches thick?0.25 cubic yardsHow much concrete for a 4×4 slab 6 inches thick?0.30 cubic yardsHow much concrete for a 4×4 slab 8 inches thick?0.40 cubic yardsHow much concrete for a 4×6 slab 4 inches thick?0.30 cubic yards
Calculated using verified formulas. Last updated March 2026.