Raised bed volume
We convert the soil depth from inches to feet, then multiply length × width × depth. For multiple beds, we calculate each bed separately and add the cubic-foot results.
Cubic feet = length (ft) × width (ft) × [depth (in) ÷ 12]
Transparent calculations
We separate formula-based math from gardening guidance. You can see the conversion, rounding, and cost rules used by the calculator below.
We convert the soil depth from inches to feet, then multiply length × width × depth. For multiple beds, we calculate each bed separately and add the cubic-foot results.
Cubic feet = length (ft) × width (ft) × [depth (in) ÷ 12]
There are 27 cubic feet in one cubic yard. We keep full precision during calculations and round only the number shown on screen.
Cubic yards = cubic feet ÷ 27
Stores sell whole bags, so a partial bag is always rounded up. This prevents the bag count from showing less volume than the plan requires.
Bags required = round up [required cubic feet ÷ bag size]
The calculator first shows the measured volume. If you select an allowance, that percentage is added only to the buying volume. We do not present any allowance as a universal recommendation.
Buying volume = calculated volume × [1 + allowance ÷ 100]
Cost comparison
We multiply the whole number of required bags by the price you enter for one bag.
Bag total = bag count × price per bag
We price the larger of your required cubic yards or the supplier minimum, then add the delivery fee.
Bulk total = order yards × yard price + delivery
Local suppliers may use different bag sizes, minimum orders, quantity increments, delivery zones, and fees. Treat the comparison as an estimate and confirm the final order with the supplier.
Gardening guidance policy
The current calculator asks you to enter soil depth directly. Future depth or planting recommendations will be added only after reviewing appropriate US University Extension, USDA, or other public horticulture resources. Recommendations will show their source and review context rather than presenting one number as a universal answer.
Use your own measurements and local prices.