CalculatorMulch
31 tools
Every calculator on this site
Mulch calculators
Mulch calculator
Bed size and depth in, cubic yards and bag counts out.
Tree ring mulch calculator
A ring is a circle with a hole in it โ and that hole is the part that saves the tree.
Mulch top-up calculator
Ordering for bare soil on a bed that is half full is how mulch ends up against the trunk.
Mulch bags calculator
Every US bag size costed side by side, so the aisle decision makes itself.
Mulch cost & bulk break-even
One delivery fee against a stack of bags โ there is a crossing point, and it moves.
Mulch depth calculator
One inch either way changes the order by a third. Only one depth is right for your bed.
Playground mulch calculator
Depth here is a safety standard, not a preference โ and it depends on how high the equipment is.
Soil & compost calculators
Soil amendment calculator
Every gardening book says amend the soil. None of them says with how much.
Compost calculator
There is a ceiling on how much compost soil can take. Most people go straight past it.
Fill dirt calculator
Loose fill and compacted fill are two different volumes. Order the wrong one and the ground sinks.
Potting soil & container calculator
Potting mix is sold in quarts and pots are measured in inches. That mismatch is the whole problem.
Raised bed soil calculator
The mix matters as much as the volume โ and one of the three ingredients has a hard ceiling.
Topsoil calculator
Soil is sold by the yard and hauled by the ton. Both numbers matter before you order.
Gravel, stone & sand
French drain gravel calculator
A trench full of gravel, minus the pipe sitting in the middle of it.
Paver base calculator
The layer that fails is never the one you can see.
Gravel calculator
Stone is priced by the ton and measured by the yard. The bridge between them is density.
Pea gravel calculator
Rounded stone that walks well at one depth and swallows your shoes at another.
River rock calculator
Coverage per ton drops fast as the stone gets bigger. That is the number the yard will not quote.
Sand calculator
Four jobs, four depths, and only one of them tolerates the cheap grade.
Conversions & cost
Bag coverage chart
Coverage is not a property of the bag. It is a property of the depth.
Bulk vs bagged calculator
Bulk is cheaper per yard and not always cheaper per job.
Cubic metres to cubic yards
Half the world buys soil by the tonne and reads advice written in yards.
Bags to cubic yards converter
The one number that makes a shelf price and a bulk quote comparable.
Cubic yards calculator
One formula sits under every material on this site, and it hinges on a single number.
Cubic yards to tons calculator
The same volume can be a light load or an illegal one. Density decides which.
Project planners Pro
Annual Mulch Budget
The yearly cost of keeping beds topped up, and what it comes to over five years โ including the labour if you are pricing a job.
Bags or Bulk: Cost Comparison
Compare bagged and bulk pricing including delivery for the volume you actually need โ the crossover point is usually lower than people expect.
Delivery and Load Planner
How many truck or trailer loads your order takes, and roughly what it weighs โ which is the limit that usually bites first.
Mulching Season Reminders
Set your spring and autumn mulching dates once and get an email before each one, year after year.
Multi-Bed Mulch Planner
Every bed in one table โ length, width and depth per bed โ adding up to the total cubic yards, cubic feet and bags you need to order.
Soil and Compost Blend Planner
Work out the volume of each component in a soil mix โ topsoil, compost, and amendment โ from the bed size and your chosen ratio.
How do you work out how much mulch you need?
Multiply length ร width ร depth in feet, then divide by 27. That last number is the whole trick: a cubic yard is a cube three feet on a side, so it holds 27 cubic feet. A 500 sq ft bed at the standard 3-inch depth works out at 500 ร 0.25 รท 27 = 4.63 cubic yards, or 125 cubic feet.
Turn that into something you can actually buy: one cubic yard covers 108 sq ft at 3 inches, and 125 cubic feet is 63 bags of the usual 2 cu ft mulch or 42 bags of the 3 cu ft size pine bark comes in. Past roughly two or three cubic yards, one delivery fee spread across a bulk load usually beats the bag price โ which is the point most calculators stop short of.
Change any input above and the answer updates as you type, and the link in your address bar carries the result with it. No sign-up, nothing stored, nothing sent anywhere.
The 27 rule
Landscaping materials are sold by the cubic yard โ a cube 3 ft on a side, so it holds 27 cubic feet. That single number turns any bed into an order.
length ft ร width ft ร depth ft รท 27 = cubic yards
One cubic yard covers
- 324 sq ftat 1″
- 162 sq ftat 2″
- 108 sq ftat 3″
- 81 sq ftat 4″
- 65 sq ftat 5″
- 54 sq ftat 6″
Every landscape material on this site is measured the same way. The bed does not care whether you are filling it with hardwood mulch, screened topsoil or #57 stone: you need its area, you need a depth, and you need to divide by 27. What changes between materials is what happens after the volume โ how much it weighs, whether it is sold by the yard or by the ton, and which bag size the store stocks it in.
The table below is the one worth memorising. It is the reason a landscaper can quote a bed from the kerb: they know a yard covers a hundred-odd square feet at the depth they use, and they count beds.
| If you order | Covers at 2 in | At 3 in | At 4 in | Weighs about |
|---|---|---|---|---|
| 1 cubic yard | 162 sq ft | 108 sq ft | 81 sq ft | 700 lb |
| 2 cubic yards | 324 sq ft | 216 sq ft | 162 sq ft | 1,400 lb |
| 3 cubic yards | 486 sq ft | 324 sq ft | 243 sq ft | 2,100 lb |
| 5 cubic yards | 810 sq ft | 540 sq ft | 405 sq ft | 3,500 lb |
| 10 cubic yards | 1,620 sq ft | 1,080 sq ft | 810 sq ft | 7,000 lb |
Weights are for dry shredded hardwood. Topsoil is roughly three times heavier for the same volume and gravel closer to four โ which matters far more for the drive home than it does for the order.
Frequently asked questions
How deep should mulch be?
Two to four inches, and three is the number to aim for on bare soil. Below two inches weed seeds still get enough light to germinate; above four, water struggles to reach the root zone and the mulch itself starts holding moisture against stems. If you are topping up mulch that is still in reasonable condition, measure what is there first and add only the difference.
How many bags of mulch are in a cubic yard?
13.5 bags of the 2 cu ft size, 9 bags of 3 cu ft, 18 bags of 1.5 cu ft, 27 bags of 1 cu ft and 36 bags of 0.75 cu ft. The maths is always 27 divided by the bag size, because a cubic yard is 27 cubic feet. Hardwood and shredded mulch usually come in 2 cu ft; pine bark and cypress in 3.
Should I remove the old mulch first?
Usually not. Mulch is supposed to break down into the soil, and stripping it out every spring throws away the organic matter you paid for. What you should do is break up any crust with a rake and measure the remaining depth: three inches of old mulch plus three inches of new is six inches, and that is where roots start to suffocate.
Can I use this calculator for topsoil, gravel or sand?
The volume half is identical for every material โ area times depth divided by 27. What changes is weight and the way it is sold: a cubic yard of mulch weighs about 700 lb, topsoil around 2,200 lb and gravel closer to 2,700 lb, and stone is often priced by the ton rather than by the yard. Use the topsoil, gravel or sand pages for those, since they carry the right density.
How much does a yard of mulch weigh?
About 700 lb dry for shredded hardwood, within a published range of 400 to 800 lb depending on the wood and how finely it is shredded. Rain changes that more than the species does: soaked mulch can weigh 20 to 40 percent more, which is what puts half-ton pickups over their payload on the drive home.
Is bagged or bulk mulch cheaper?
Bulk is cheaper per cubic yard almost everywhere โ often $35 to $50 a yard against $75 to $90 a yard once you buy the same volume in 2 cu ft bags. Delivery is what flips it. One drop-off fee of $50 to $85 spread over a single yard is a bad deal and spread over five is a rounding error, so the crossover usually lands around two to three yards.
What the yard needs this month
MonthlyOne job a month, with the depth and the volume it actually needs. No plant catalogues, no upsell โ just the material side of the garden.
How we calculate this
Worked example
With Length ft 24, Width ft 15, Diameter ft 12, Base ft 20, Height ft 12, Area sq ft 300, Ring diameter ft 6, Gap around trunk (in) 4, Depth 3, $ per bag (optional) 6.50, this page works out 3.3 cubic yards. = 90 cu ft ยท about 45 bags ( 2 cu ft )
- Bagged cost at that price$292.50
- One cubic yard covers108 sq ft at this depth
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