Biology
Work out how much mulch you need for a bed or area, in cubic yards, cubic feet, litres and bags.
Your inputs
Change any value — everything updates instantly.
Longest side of the area.
Shorter side of the area.
2–4 inches is typical for beds.
Same-size areas to fill.
Try an example
Mulch needed
0.37 cubic yards
This means you need about 0.37 cubic yards — roughly 5 bags of 2 cubic feet each.
What you are seeing
The box shows your area, 10 × 4 ft.
It fills with mulch to 3 inches deep.
That fill is 10 cubic feet in total.
Cubic feet
10 ft³
Volume in cubic feet.
Litres
283 L
Same volume in litres.
2 ft³ bags
5 bags
Rounded up to whole bags.
1.5 ft³ bags
7 bags
If you buy smaller bags.
Area covered
40 ft²
Total surface you are covering.
Result explanation: How much mulch to buy
0.37 yd³ (0.28 m³).
Real-life comparison: Bags are usually easiest for small amounts like this.
Low, normal or high? Keep mulch a few inches away from stems and trunks.
Volume needed against depth
How to read this chart: Each extra inch adds the same amount. The red dot is your depth.
Multiplies area by depth to find how much mulch fills the space.
0.37 cubic yards.
5 bags of 2 ft³.
Buy 5–10% extra for settling and uneven ground.
Inches ÷ 12 makes every length feet; ÷ 27 converts to cubic yards.
ft³ = length × width × (depth ÷ 12) × beds; yd³ = ft³ ÷ 27
Symbols
Why this formula works
A bed is a box; its volume is length × width × height.
Unit check
ft × ft × ft = ft³; 27 ft³ = 1 yd³ ✓
Worked example
Common mistakes
You need 0.37 cubic yards of mulch.
A cube 3 ft on every side — 27 cubic feet, about 765 litres.
Yes, 5–10% extra covers settling and uneven ground.
Split the shape into rectangles and add them, or use the average length and width.
Loose soil and compost settle over weeks; you may need a top-up.
Reviewed 2026-09-25 · Next review 2027-09-25
Important limitation. Planning estimate. Supplier bag sizes and settling vary.
Tell us if a formula, unit, explanation, or result needs attention. Your message will include this calculator’s name and page.
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