Raised Bed Soil Calculatorv1.0.0

Plan how much soil, compost, and amendments to buy for one raised garden bed or a whole garden of mixed-size beds. Enter each bed's dimensions, choose a soil mix recipe, and receive total volume in cubic feet and cubic yards, approximate weight, bag counts, and material cost. Supported shapes include rectangular, circular, and L-shaped beds, with both imperial and metric units.

• Select a Unit System at the top of the form. Choose Imperial for feet, inches, and pounds or Metric for meters, centimeters, and kilograms.
• Choose a Bed Shape for each bed. Rectangular beds use length and width; circular beds use a single diameter value in the Width field; L-shaped beds apply a 75% area factor to the bounding rectangle.
• Enter the Width and Length of the bed. These fields accept decimals (3.5), fractions (7/2), and mixed numbers (3 1/2).
• Enter the Height / Depth of the bed. Most vegetables need 6 to 12 inches (15 to 30 cm) of soil depth.
• Set Quantity if you have several identical beds of this exact size. Each bed's quantity multiplies its own volume in the total.
• Click Add Another Bed to enter a bed with different dimensions or a different shape. Use Remove Bed on any row to delete it. Volumes from every bed are summed in the total.
• Select a Soil Mix Recipe. Use 60/40 topsoil-to-compost for most vegetables, Mel's Mix for square foot gardening, or Custom to set your own percentages.
• Click Calculate to view total volume, weight, bag counts, estimated cost, and a soil mix breakdown. Results update automatically as you type.
• Open Settings to adjust cost per cubic foot for each material, soil weight, or to enable the step-by-step formula display.
• Click Reset to clear every bed, remove saved state, and return to a single default bed.

Per-bed volume formulas: Rectangular = Length x Width x Height, Circular = pi x (Diameter / 2) squared x Height, L-Shaped = 0.75 x Length x Width x Height. Each volume is multiplied by Quantity and then summed across all beds. Weight defaults to 40 lbs per cubic foot, and cubic yards equal cubic feet divided by 27.

Plan a raised bed project with accurate soil estimates before purchasing materials. Mix rectangular, circular, and L-shaped beds in one combined estimate to prevent over-buying or running short on soil and amendments.

• Backyard Gardening: Determine how many bags of soil to buy for a standard 4 x 8 foot raised bed and compare bagged versus bulk delivery costs.
• Mixed-Size Gardens: Add a row for two 4 x 8 rectangular beds (Quantity 2), a 6-foot diameter round herb bed, and an L-shaped corner bed. The total cubic-yard figure is your bulk order.
• Square Foot Gardening: Select the Mel's Mix recipe (1/3 compost, 1/3 peat moss, 1/3 vermiculite) and calculate exact quantities for each component. Use the cost settings to compare prices from different suppliers.
• Community Gardens: Add a row for every plot size and set its quantity. Split the cumulative cost fairly across members using the breakdown.
• Landscaping Projects: Use the circular bed shape for round planters or tree rings, then add rectangular rows for adjacent borders. Switch to metric units when projects use metric lumber and soil measurements.
• Budget Planning: Adjust the cost per cubic foot in Settings to match local pricing. Compare the total cost of different soil mix recipes before committing to a purchase.
• Season Preparation: Calculate how much additional compost to add each spring. Soil settles 10 to 15 percent in the first season, so plan to top off beds annually with a compost layer.
• Hugelkultur Beds: For beds deeper than 12 inches, estimate soil volume for the top 12 inches and fill the bottom with logs, sticks, or leaves to reduce cost and improve drainage.
• Education: Teach students about volume calculations using real garden dimensions. Enable the step-by-step formula display to show the math behind each bed and the running total.