Mulch Calculator: How Much Mulch Do I Need? (Yards, Bags)

How to use the mulch calculator

Pick Feet / inches or Metres / cm. Switching converts the sizes you already typed.
Pick the shape: Bed (length and width), Circle (diameter), Tree ring (how far across, and the gap you leave around the trunk) or Area if you already know the square feet or square metres. For a curved or L-shaped bed, split it into rectangles and circles, work out each one and add them up.
Enter the depth, or tap a preset: 1 in (2.5 cm) to top up last year's mulch, 2 in (5 cm) for flower beds, 3 in (7.5 cm) for shrubs and tree rings, 4 in (10 cm) for paths.
Choose your bag size. Most US bags hold 2 cu ft; 1.5 and 3 cu ft bags are common too. In metric, bags are sold in litres (50, 60, 75 or 100 L).
Leave +10% extra on unless you have a reason to change it (see how much extra to order, below). Add a price per cubic yard (or cubic metre) and a price per bag to compare bulk with bags.
Read the answer: cubic yards (or cubic metres) for a bulk delivery, and the number of bags for a trip to the garden centre.

The results are estimates for loose mulch. Bagged mulch is packed tight and fluffs up when you open it, and every mulch settles after a few rains, which is part of why the calculator adds 10%.

Mulch calculator formula: cubic yards and bags

In US units, with the depth in inches:

Cubic yards = area (sq ft) × depth (in) ÷ 324
Cubic feet = area (sq ft) × depth (in) ÷ 12
Bags = cubic feet ÷ bag size (2 cu ft for most bags), rounded up

Example: a 10 × 10 ft bed at 3 in deep is 100 × 3 ÷ 324 = 0.93 yd³, or 25 ft³, which is 12.5 bags of 2 cu ft. With 10% extra: 1.02 yd³ (27.5 ft³), so 14 bags of 2 cu ft or 10 bags of 3 cu ft.

In metric, with the depth in centimetres:

Cubic metres = area (m²) × depth (cm) ÷ 100
Litres = cubic metres × 1,000; bags = litres ÷ bag size, rounded up

Example: a 3 × 3 m bed at 7.5 cm deep is 9 × 7.5 ÷ 100 = 0.68 m³. With 10% extra: 0.74 m³ (743 litres), so 15 bags of 50 litres.

For a circle, the area is 3.14 × radius² (half the diameter, squared). For a tree ring, take the area of the whole circle and subtract the small circle you leave bare around the trunk; the Tree ring shape in the calculator does that for you.

How deep should mulch be? Depth by area

Depth changes the answer more than anything else: going from 2 to 3 inches needs half as much mulch again. These are the depths the calculator guides we read recommend.

Recommended mulch depth by area (CalculatorSoup, LawnStarter, Almanac)
Area	Depth	Notes
Top-up of existing mulch	1–2 in (2.5–5 cm)	Top up when the old layer is thinner than about 2 in
Flower beds	2–3 in (5–7.5 cm)	Fine mulch at the low end, coarse bark at the high end
Shrub and foundation beds	2–3 in (5–7.5 cm)	Keep it a few inches back from the stems
Tree rings	2–4 in (5–10 cm)	Flat, like a doughnut, 3–6 in (8–15 cm) back from the trunk; never piled up against the bark
Vegetable beds	1–2 in (2.5–5 cm) settled	Straw goes down 4–6 in loose and settles to about 2 in
Paths and play areas	3–4 in (7.5–10 cm)	Coarse wood chips; they pack down under foot traffic

Three of these as pictures, with the sums for each. The left image of each pair was generated by AI as a stand-in for an ordinary yard, and the right image is that same picture edited by AI from a written instruction. They are not photos of real homes; we made them with our own AI model, which is not one of the models you can pick in the landscape tool. All three were run a second time, as their captions say.

AI-generated example: a maple tree in a suburban front lawn with thin worn grass and bare soil around exposed roots at the base of the trunk, houses and a driveway behind — Already in the before: the maple, the worn patch with roots showing and the houses behind. What followed the instruction: a wide round ring of dark brown shredded bark with a clean cut edge to the lawn, and the bare patch is covered. This is the second run: on the first, the ring still looked like bare soil with roots on top. What it changed that we did not ask for: the camera moved closer, the houses behind changed and the trunk is thinner. The mulch also looks as if it reaches the trunk; in a real yard keep it 3–6 inches away so the trunk flare stays dry.

AI-edited version of the image: a large round ring of dark brown shredded bark mulch around the tree with a clean edge to the lawn, seen from a closer, different angle — Already in the before: the maple, the worn patch with roots showing and the houses behind. What followed the instruction: a wide round ring of dark brown shredded bark with a clean cut edge to the lawn, and the bare patch is covered. This is the second run: on the first, the ring still looked like bare soil with roots on top. What it changed that we did not ask for: the camera moved closer, the houses behind changed and the trunk is thinner. The mulch also looks as if it reaches the trunk; in a real yard keep it 3–6 inches away so the trunk flare stays dry.

AI-generated example: a backyard with a muddy dirt footpath curving across patchy grass toward a small wooden shed, with a wooden fence and trees behind — Already in the before: the shed, the fence, the trees, the patchy grass and the muddy track. What followed the instruction: the mud is gone and the path is one even layer of chunky wood chips along the same curve to the shed. This is the second run: on the first, the path still looked like packed dirt. The chips came out a bright orange; fresh arborist chips are often that colour and fade to grey-brown within a season.

AI-edited version of the same image: the muddy footpath replaced by a curving path of orange-brown wood chips leading to the shed — Already in the before: the shed, the fence, the trees, the patchy grass and the muddy track. What followed the instruction: the mud is gone and the path is one even layer of chunky wood chips along the same curve to the shed. This is the second run: on the first, the path still looked like packed dirt. The chips came out a bright orange; fresh arborist chips are often that colour and fade to grey-brown within a season.

AI-generated example: two wooden raised beds with young tomato plants and lettuce in bare dry soil with small weeds, grass and bare ground around them and a wooden fence behind — Already in the before: the two wooden beds, the tomatoes and lettuce, the weedy ground and the fence. What followed the instruction: golden straw covers the soil inside both beds around the plants. What it did not follow: we asked for straw only inside the beds, and some also spilled onto the ground around them. This is the second run: on the first, the straw went around the outside of the beds and the soil inside stayed bare. Use straw, not hay, which carries seeds.

AI-edited version of the same image: golden wheat straw mulch around the tomato and lettuce plants inside both raised beds, with some straw also on the ground around the beds — Already in the before: the two wooden beds, the tomatoes and lettuce, the weedy ground and the fence. What followed the instruction: golden straw covers the soil inside both beds around the plants. What it did not follow: we asked for straw only inside the beds, and some also spilled onto the ground around them. This is the second run: on the first, the straw went around the outside of the beds and the soil inside stayed bare. Use straw, not hay, which carries seeds.

Mulch colours: the same bed in black, brown, red, cedar and pine straw

The amount of mulch is the same whatever the colour; the look is not. Here is one foundation bed, a 30 × 4 ft strip, which needs 1.22 yd³ at 3 inches with 10% extra (17 bags of 2 cu ft). The first picture was generated by AI as the bare bed, and each of the others is that same picture edited by AI to add one mulch. A few weeds from the before still poke through in every version, which real weeds would also do without pulling them first.

AI-generated example: a curved planting bed along the tan siding of a house, with four round boxwoods and two blue hydrangeas in bare dark soil with small weeds, and a lawn in front — **Before.** Bare soil with weeds, black edging and a lawn in front.

AI-edited version of the bed: the bare soil covered with deep black shredded mulch around the boxwoods and hydrangeas — **Black.** Dyed black mulch gives the strongest contrast with green leaves and light siding. Dark mulch warms up in full sun, and dyed colours fade over a season.

AI-edited version of the bed: the bare soil covered with dark brown shredded hardwood mulch around the boxwoods and hydrangeas — **Dark brown.** The most natural look; it reads like rich soil. In our picture it is close to the colour of the bare soil in the before, and a few weeds still poke through. This is the second run: the first came out red-brown.

AI-edited version of the bed: the bare soil covered with bright red dyed shredded mulch around the boxwoods and hydrangeas — **Red.** Dyed red mulch stands out against tan or grey siding and green shrubs. It is the boldest choice and the one people most often regret on a red-brick house.

AI-edited version of the bed: the bare soil covered with light golden-tan shredded cedar mulch around the boxwoods and hydrangeas — **Natural cedar.** Undyed cedar is light golden-tan and smells of cedar. It turns silver-grey as it weathers, which some people like and some top up to avoid.

AI-edited version of the bed: the bare soil covered with a reddish-brown mat of pine straw around the boxwoods and hydrangeas — **Pine straw.** Long dry pine needles, common in the US South. Our picture reads more like fine reddish-brown mulch than long needles. Pine straw is sold in bales, not by the cubic yard, so ask your supplier how much area one bale covers.

To pick a colour for your own house, upload a photo of your beds and try two or three of them side by side.

See mulch on my yard photo

How much does a yard or a bag of mulch cover?

If you already have a load or a pallet of bags in mind, work backwards. Coverage is the same for every mulch, because it is a volume.

Coverage in US units
Depth	1 cubic yard	1 bag of 2 cu ft	1 bag of 3 cu ft
1 in	324 sq ft	24 sq ft	36 sq ft
2 in	162 sq ft	12 sq ft	18 sq ft
3 in	108 sq ft	8 sq ft	12 sq ft
4 in	81 sq ft	6 sq ft	9 sq ft

Coverage in metric units
Depth	1 m³	1 bag of 50 L	1 bag of 75 L
2.5 cm	40 m²	2 m²	3 m²
5 cm	20 m²	1 m²	1.5 m²
7.5 cm	13.3 m²	0.67 m²	1 m²
10 cm	10 m²	0.5 m²	0.75 m²

Bags in a cubic yard (or a cubic metre)
Bag size	Bags
1.5 cu ft	18
2 cu ft	13.5 (buy 14)
3 cu ft	9
50 L (per m³)	20
75 L (per m³)	13.3 (buy 14)

How much extra mulch to order

The calculator adds 10% by default. Beds are never perfectly measured, curved edges take more than you think, and fresh mulch settles after the first rains. Running short in the middle of a bed means a second trip or a second delivery charge.

+5%: a simple rectangle you measured carefully.
+10%: most beds, tree rings and paths.
+15–20%: curvy beds, slopes, or shredded bark, which mats and settles more than chips.

Bagged vs bulk mulch, and what mulch costs

Garden centres sell mulch in bags, mostly 2 cu ft in the US (1.5 and 3 cu ft too) and 50–100 litres in the UK and Europe. Landscape supply yards sell bulk mulch by the cubic yard (or cubic metre) and deliver it by truck.

Bagged mulch: about $3–$8 per 2 cu ft bag, or roughly $44–$112 per cubic yard's worth of bags.
Bulk mulch: about $30–$135 per cubic yard before delivery, depending on the type; dyed and cedar cost more than plain hardwood.
Delivery: often free from about 5 cubic yards.

LawnStarter's example: 5 cubic yards cost about $210 in bulk and about $228 as 68 bags. The gap grows with the job, and bulk saves dozens of plastic bags. These are US ranges from the guides below; enter your own supplier's prices in the calculator.

See mulch on a photo of your own yard

Before you buy a truckload, check the colour against your house. Upload a photo of your beds to our AI landscape tool, choose Custom and describe the mulch: the colour, where it goes and what must stay the same. For bed ideas, see our flower bed ideas and foundation planting ideas; for stone instead of mulch, use the gravel calculator.

See mulch on my yard photo

1 free render with a free account (sign in with Google or an email code). More renders come with a paid plan (see pricing).

Mulch calculator questions

How do I calculate how much mulch I need?

Multiply the area in square feet by the depth in inches and divide by 324 to get cubic yards (324 = 27 cubic feet in a yard × 12 inches in a foot). For bags, multiply the area by the depth in inches, divide by 12 to get cubic feet, then divide by the bag size. In metric, multiply the area in m² by the depth in cm and divide by 100 to get cubic metres; × 1,000 gives litres. Add about 10%.

How much mulch do I need for a 10 × 10 area?

At 3 inches deep: 100 sq ft × 3 ÷ 324 = 0.93 cubic yards, or 25 cubic feet, which is 13 bags of 2 cu ft. With 10% extra, about 1 cubic yard or 14 bags. At 2 inches, about two thirds of that: 0.62 yd³ or 10 bags with the extra.

How many bags of mulch are in a yard?

13.5 bags of 2 cu ft (27 ÷ 2), so buy 14. It is 9 bags of 3 cu ft and 18 bags of 1.5 cu ft. In metric, a cubic metre is 20 bags of 50 litres or about 13.3 bags of 75 litres.

How much does a yard of mulch cover?

324 sq ft at 1 inch, 162 sq ft at 2 inches, 108 sq ft at 3 inches and 81 sq ft at 4 inches. A 2 cu ft bag covers 12 sq ft at 2 inches and 8 sq ft at 3 inches. A cubic metre covers 20 m² at 5 cm.

How deep should mulch be?

About 2–3 inches (5–7.5 cm) for flower and shrub beds, 2–4 inches for tree rings, 3–4 inches (7.5–10 cm) for paths and 1–2 inches to top up an old layer. Fine mulch can be thinner and coarse bark thicker. Deeper than about 4 inches can starve roots of air and water, and mulch piled against a trunk or stems invites rot.

Is it cheaper to buy mulch in bags or in bulk?

Bulk is usually cheaper per cubic yard once you need more than one or two yards, even with the delivery charge, and many suppliers deliver free from about 5 cubic yards. Bags make sense for one or two small beds, for a car with no trailer, or where bulk delivery is not available.

How much does a bag or a yard of mulch weigh?

A 2 cu ft bag of wood mulch weighs about 20 lb and a 3 cu ft bag about 30 lb. A cubic yard weighs roughly 400–800 lb, depending mostly on how wet it is. That is why mulch is sold by volume, not weight; this calculator works in volume only.

Can I see a mulch colour on my own yard before I buy?

Yes. Upload a photo of your beds to the landscape tool, choose Custom and describe the mulch (black, dark brown, red, natural cedar or pine straw) and what must stay the same. It is a picture for planning, not a measured drawing. You need a free account: 1 free render with a free account, and free renders carry a watermark.

Sources for the depths, coverage and prices

Read on 11 November 2026.

Mulch Calculator: How Much Mulch Do I Need?