Compost Coverage Calculator

Know how far compost spreads before you buy. Choose shapes, units, and application depth instantly. Get cubic yards, bag counts, and cost totals fast.

Calculator

Pick the bed shape you can measure.
Used for rectangle/circle dimensions.
Preset overwrites the depth fields.
Used when area method is rectangle.
Used when area method is rectangle.
Used when area method is circle.
Used when area method is custom.
Applies to custom area only.
Typical compost layer: 0.5–3 inches.
Use inches for most garden applications.
Accounts for settling after watering and raking.
Extra margin for uneven coverage and losses.
Choose a bag option to estimate bag count.
Used when bag sizing is standard.
Used when bag sizing is custom.
Example: USD, EUR, PKR.
Optional: estimate cost by bags.
Optional: estimate cost by bulk delivery.
Reset

Example data

Scenario Area Depth Allowances Adjusted Volume Approx. Bags (2 cu ft)
Vegetable bed 10 ft × 6 ft 2 in 10% compaction, 5% waste ~1.42 cu yd ~20
Tree ring 8 ft diameter 1 in 10% compaction, 5% waste ~0.60 cu yd ~9
Lawn topdress 500 ft² 0.5 in 10% compaction, 5% waste ~0.89 cu yd ~12

Formula used

  • Area: Rectangle = L × W. Circle = π × (D/2)². Custom area uses your entered value.
  • Base volume: V = Area × Depth.
  • Allowances: V_adjusted = V × (1 + Compaction% + Waste%).
  • Unit conversions: 1 cu yd = 27 ft³, 1 m³ ≈ 35.3147 ft³, 1 L ≈ 0.0353147 ft³.
  • Bags: Bags = ceil(V_adjusted / BagVolume).

How to use this calculator

  1. Select an area method that matches your garden section.
  2. Enter dimensions (or custom area) and choose units.
  3. Set the compost layer depth, or pick a preset.
  4. Adjust allowances if you expect settling or uneven beds.
  5. Select a bag size to estimate bag counts, and optionally costs.
  6. Press Calculate. Use the download buttons for records.

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Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.