How to calculate it yourself
Total cubic feet of concrete from a pallet = (bag yield × bag count). A 60 lb bag yields 0.45 cu ft; 80 lb bag yields 0.6 cu ft. A standard 80 lb pallet (42 bags) makes 25.2 cu ft of mixed concrete = 0.93 cubic yards.
Common scenarios
Small DIY footing job (0.5 yd³)
Half a pallet of 80 lb bags (~22 bags) is plenty. Most home centers will sell partial pallets at the regular bag price.
Patio pour (1 yd³)
One full pallet of 80 lb (42 bags) yields 0.93 yd³ — slightly under target. Buy 45 bags or one pallet plus a few extra.
Multi-day project (3+ yd³)
Three pallets of 80 lb (126 bags). At this volume, ready-mix delivery is almost always cheaper unless mixing access is impossible.