20×10 ft bed at 3 in
Input
20 ft × 10 ft × 3 inOutput
50 cu ft · 1.85 cu yd · 25 bags at 2 cu ft20 × 10 × 3 ÷ 324 = 1.85 cu yd. Bags: ceil(50 ÷ 2) = 25.
Mulch volume is **area × depth**. For US gardeners, measure length and width in feet and depth in inches.
**Imperial formula (rectangle):**
Cubic yards = Length (ft) × Width (ft) × Depth (in) ÷ **324**
Equivalently: Cubic feet = Length × Width × Depth (in) ÷ 12, then ÷ 27 for yards.
**Example — 20×10 ft bed, 3 in deep:**
20 × 10 × 3 ÷ 324 = **1.85 cubic yards** (50 cu ft)
**Area-only mode:** If you already know total square footage (from a tape measure or plat), multiply area (sq ft) × depth (in) ÷ 12 for cubic feet, then ÷ 27 for yards.
**Coverage shortcut:** At 3 in depth, **1 cubic yard covers ~108 sq ft**. At 2 in, one yard covers ~162 sq ft. At 4 in, ~81 sq ft.
**Metric formula:**
Volume (m³) = Area (m²) × Depth (cm) ÷ 100
**Example — 20 m² at 7 cm:**
20 × 0.07 = **1.4 m³** (1,400 liters)
Bulk mulch is sold by the **cubic yard** for truck delivery. Bagged hardwood mulch is labeled in **cubic feet** (1, 1.5, 2, or 3 cu ft). Add **5–15% extra** for settling after rain, wheelbarrow spillage, and uneven beds.
The calculator treats the mulched zone as a flat rectangular prism (or known area × depth). An optional buffer increases the order quantity for real-world loss.
Formula
cu yd = L(ft) × W(ft) × D(in) ÷ 324 | cu ft = area(sq ft) × D(in) ÷ 12 | m³ = area(m²) × D(cm) ÷ 100Use Quick presets for common beds and tree rings, or enter length × width, total square footage, or ring diameter. Measure the mulched zone only — not paths or lawn.
Tap a depth preset: 2 in for a color refresh, 3 in for new beds and weed suppression, or 4 in only where weeds are aggressive. Pull mulch 2–4 in away from trunks and stems.
Bulk suppliers quote by the cubic yard. The results panel shows a bulk vs bag recommendation based on your total volume — round up for delivery minimums.
Enter your bag size (2 cu ft is common for hardwood mulch) on the main form. Bag count rounds up to whole bags. Open Advanced for coverage tables at your depth.
Enable the buffer on the main form for first-time installs or steep slopes. Ten percent is the default; light refresh layers may need none.
Input
20 ft × 10 ft × 3 inOutput
50 cu ft · 1.85 cu yd · 25 bags at 2 cu ft20 × 10 × 3 ÷ 324 = 1.85 cu yd. Bags: ceil(50 ÷ 2) = 25.
Input
200 sq ft × 3 inOutput
50 cu ft · 1.85 cu ydSame volume as 20×10 — area × depth ÷ 12 = cu ft.
Input
1000 sq ft × 2 inOutput
166.7 cu ft · 6.17 cu yd1000 × 2 ÷ 12 = 166.7 cu ft. ÷ 27 = 6.17 yards — bulk delivery territory.
Input
⌀ 8 ft × 3 inOutput
12.6 cu ft · 0.47 cu yd · 7 bags at 2 cu ftπ × (4 ft)² × 0.25 ft = 12.57 cu ft. Bags: ceil(12.57 ÷ 2) = 7.
Input
20 m² × 7 cmOutput
1.4 m³ · 1,400 L20 × 0.07 m depth = 1.4 cubic meters.
Common real-world scenarios where this tool saves time.
A 20×10 ft bed at 3 in depth needs ~1.85 cu yd. Ordering 2 yards with a 10% buffer covers spillage. At 2 cu ft per bag, plan for 25–28 bags.
Top-dress 200 sq ft at 2 in: 200 × 2 ÷ 12 = 33.3 cu ft → ~1.23 cu yd. A single bulk pickup or ~17 two-cubic-foot bags.
Use Tree ring (⌀) mode: an 8 ft diameter ring at 3 in needs about 12.6 cu ft (~0.47 cu yd). Keep depth 2–3 in and avoid volcano mulching against the trunk.
EU gardeners enter m² and cm for direct m³ and liter readouts — useful when suppliers quote bulk bags in litres.
Step-by-step chains that connect related tools for common tasks.
From measurement to delivery in four steps.
Square feet one loose cubic yard covers at even depth.
| Depth | Sq ft per cu yd | Typical use |
|---|---|---|
| 1 in | 324 | Color refresh on existing mulch |
| 2 in | 162 | Annual top-dressing |
| 3 in | 108 | New beds · weed suppression |
| 4 in | 81 | Heavy weed areas · playgrounds |
Formula: 324 ÷ depth (inches) = sq ft per cubic yard.
Approximate coverage per bag and bags needed per cubic yard.
| Bag size | Covers (sq ft) | Bags per cu yd |
|---|---|---|
| 1 cu ft | 4 | 27 |
| 1.5 cu ft | 6 | 18 |
| 2 cu ft | 8 | 14 |
| 3 cu ft | 12 | 9 |
Coverage = bag cu ft ÷ (depth in ÷ 12). Round bag orders up.
Choose format based on volume, access, and labor.
| Volume needed | Best format | Trade-off |
|---|---|---|
| Under 1 cu yd (~27 cu ft) | Bagged retail | Higher $/cu ft, no delivery minimum |
| 1–3 cu yd | Compare bulk vs pallet | Delivery fee vs bag sale + your labor |
| 3+ cu yd | Bulk truck delivery | Lowest $/cu yd; needs driveway or tarp drop |
Prices vary by region, dyed vs natural, and hardwood vs bark.
| Depth | Imperial | Metric equivalent | Best for |
|---|---|---|---|
| Light refresh | 1–2 in | 2.5–5 cm | Color boost on existing mulch |
| Standard install | 3 in | 7–8 cm | Weed suppression · moisture retention |
| Heavy weed barrier | 4 in | 10 cm | Aggressive weeds — not for plant crowns |
| Too deep (avoid) | 6+ in | 15+ cm | Root suffocation · pest habitat |
One cubic yard equals **27 cubic feet**. Ordering 50 cu ft is under 2 yards, not 50 yards.
Piling mulch against trunks traps moisture and causes bark rot. Use a donut shape — thin at the trunk, deeper at the drip line.
Pull weeds or apply pre-emergent first. Deep mulch on top of weeds only delays regrowth.
Measure the **planted area** you will actually mulch, not fence-to-fence if paths are included.
Thick mulch blocks oxygen to roots. Refresh thin layers annually instead of piling high.
The calculator handles conversion. Manual math: divide depth in inches by 12 before multiplying by area in sq ft.
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At 3 in depth, 10×10 ft = 100 sq ft. Volume = 100 × 3 ÷ 12 = 25 cu ft, or about 0.93 cubic yards. Round up to 1 yard for bulk or 13 bags at 2 cu ft each.
One cubic yard = 27 cu ft. Divide 27 by bag size: ~14 bags at 2 cu ft, ~18 at 1.5 cu ft, ~9 at 3 cu ft. Always round up — partial bags are not sold.
Divide 324 by depth in inches. At 3 in, one yard covers 108 sq ft. At 2 in, 162 sq ft. At 4 in, 81 sq ft.
2–4 inches (5–10 cm) for most ornamental beds. Three inches is the sweet spot for weed suppression without blocking air to roots. Pull back from trunks and building foundations.
For mulch beds: cubic yards = length (ft) × width (ft) × mulch depth (in) ÷ 324. Area-only: (square feet × depth in inches ÷ 12) ÷ 27. Typical depth is 2–4 in, not fill depth.
Bag cu ft ÷ (depth in ÷ 12). A 2 cu ft bag at 3 in covers about 8 sq ft. A 1.5 cu ft bag at 3 in covers about 6 sq ft.
Under ~1 cubic yard, bags are simpler. Above 2–3 cubic yards, bulk delivery usually costs less per cubic foot if you can receive a truck dump and wheelbarrow it in.
Spring after soil warms (weed suppression before summer) and fall after first frost (insulation in cold zones). Avoid fresh mulch against frozen or waterlogged soil.
A 4×8 ft surface at 3 in depth = 32 × 3 ÷ 12 = 8 cu ft — only 0.3 cu yd. Mulch on raised beds is usually a thin top layer; use our Raised Bed Soil Calculator for fill soil volume inside the frame.
Switch to Tree ring (⌀) mode and enter the outside diameter in feet. An 8 ft ring at 3 in depth needs about 12.6 cu ft (0.47 cu yd). For irregular rings, use total area mode with your best square-foot estimate.
Volume math is identical, but rubber mulch is often installed 1–2 in deep (not 3–4 in). Check manufacturer coverage charts for weight and depth limits.
Mulch bed dimensions and depth values are processed only in your browser — EverydayTools does not collect or store your garden measurements.
Volume estimates only — not landscape contracting, structural, or commercial quantity surveying. Confirm order quantities with your supplier.
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Reviewed on 2026-06-27.
Mulch depth presets
2 in for refresh; 3 in standard; 4 in for weed suppression — keep away from trunks.
Bagged mulch — often 2.0 cu ft at big-box stores. Leave blank to skip bag count.
1 cubic yard covers
| Depth | Sq ft |
|---|---|
| 1 in | 324 |
| 2 in | 162 |
| 3 in | 108 |
| 4 in | 81 |
Bag coverage at 3 in depth
| Bag | Covers | Per cu yd |
|---|---|---|
| 1 cu ft bag | 4 sq ft | 27 bags |
| 1.5 cu ft (40 L) | 6 sq ft | 18 bags |
| 2 cu ft bag | 8 sq ft | 14 bags |
| 3 cu ft bag | 12 sq ft | 9 bags |