Mulch Calculator – Calculate the amount of mulch required for rectangular, circular and triangular garden beds in cubic yards, cubic feet and bags. Use live cost estimates as you type for budgeting for bagged or bulk mulch.
0.56
cubic yards
15.0
cubic feet
8
bags (2 cu ft)
$36.00
estimated cost
Compare bags by size
Whole bags needed for this project
| Bag size | Bags needed | Coverage per bag |
|---|
How Much Mulch Do I Need?
To determine garden bed size in cubic feet, multiply garden bed area by mulch depth (in feet). Use 27 to divide when you need cubic yards. One 2 cubic foot bag will cover approximately 8 square feet at 3 inches. Fill in the calculator below to include your bed shape, bag size, waste allowance, and price.
What is a Mulch Calculator?
A mulch calculator takes the area of the garden bed and the desired mulch depth and calculates the volume needed (usually in cubic yards, or cubic feet for bagged mulch). Bark, wood chips and shredded hardwood are sold by the cubic yard in bulk quantities, or by the bag which typically contains 1.5, 2 or 3 cubic feet. Those two units are far from common-sense, which is why nearly every gardener under or over buffs at least once. This tool takes out the guess work: You enter your bed dimensions and depth, and it tells you the volume and how many bags to purchase.
The maths is simple. Cubic Feet = Area (in square feet) x Depth (in feet). Dividing cubic feet by 27 converts to cubic yards — one cubic yard is a 3×3×3-foot block. The bag count is obtained by dividing by the volume of the bag. The only shape specific step is measure bed area (which varies according to footprint).
How to Use This Mulch Calculator
- Choose a type of bed. Select the appropriate shape of your area to be covered, whether it be a rectangle, circle or triangle.
- Enter the dimensions in feet. Length and width of a rectangle, diameter (not radius) of a circle, or base and height of a triangle.
- Choose your depth. A 2 inch layer is good to refresh existing beds, 3 inches is the recommended amount of mulch to be applied to new beds over soil, 4 inches or more will provide better weed suppression, but will be higher cost.
- Decide on an amount and cost for the bag. The standard retail bag size is 2 cubic feet, other common sizes are listed on the tool and cost per bag can be compared.
- Read the results. Volume is displayed in cubic yards, cubic feet, and bags (if a cost per bag is entered, a live cost estimate will appear).
Mulch Depth: The Number that Drives Everything
The greatest lever on your total is depth. If you use 2 inches, you’ll double your volume and your bill, if you use 4 inches you’ll double your volume and your bill again. When standing in the garden center aisle without a calculator, the table below gives the percentage coverage, at each depth, of a single 2-cubic-foot bag.
| Depth | Coverage per 2 cu ft bag | Character |
|---|---|---|
| 1 in | 24 sq ft | Thin refresh |
| 2 in | 12 sq ft | Standard top-up |
| 3 in | 8 sq ft | Recommended for beds |
| 4 in | 6 sq ft | Heavy weed suppression |
| 6 in | 4 sq ft | Deep new bed |
Use Cases for a Mulch Volume Calculator
Planning a mulching project for the weekend – Knowing the volume in cubic yards before you rent a truck or order from a landscape supplier will help you to compare the two options—bulk delivery and bagged pickup. The only time bulk is cheaper per cubic foot is when you can fill the entire truckload, so be sure to check the numbers before making the purchase.
Planning a landscaping project – A cubic yard estimate is the industry standard language used for the work, whether it is done in-house or a quote is requested. You’ll be able to see the supplier prices side by side and identify any hidden items.
Mulching the soil around trees and shrubs – The classic case for the circle option is the circular tree rings. This calculator measures the diameter once and you will never again have to guess what it takes to go around the tree in “how many bags around the tree” again.
Mulching Like a Pro: Pro Tips for a Great Job
- Buy 5–10% extra. Most pros put in a little extra above the volume calculated, and mulch also covers and compacts a couple of thin spots.
- Get a wheel barrow man or woman. A cubic yard is approximately 13–14 bags of standard size bags and will weigh between 400-600 lbs depending on moisture content — heavy!
- Minimize depth, especially near stems (less than 3 inches). Mulching around tree trunks in a “volcano” style keeps moisture from evaporating and encourages rot and insect infestation. Maintain a distance and make it thinner at the bottom.
- Take measurements from the present bed, not your past one. Beds expand and contract as planting and weeding takes place; a single pass around the field with a tape measure is cost effective.
- Use coarse chips or bark on slopes. Slopes can wash and blow finer shredded mulch away.
Related Tools
FAQ
How many cubic yards of mulch are in a bag?
There are 27 cubic feet in a cubic yard. This is 13.5 bags of 2 cubic feet mulch, 18 bags of 1.5 cubic feet mulch or 9 bags of 3 cubic feet mulch. Always round UP to the whole bag.
How many cubic feet of mulch can be obtained in a yard?
Exactly 27. A cubic yard is a cube 3 feet long, 3 feet wide and 3 feet high. All volume conversions for landscaping are based on this number of 27.
Is 3″ of mulch too much?
If you’re putting a new layer on top of the soil, 3 inches is where it’s in the sweet spot — just enough to help keep weeds out of the way and to keep the soil moist. When adding to an existing layer, it may be best to keep it at about 2 inches as the old layer is present underneath.
How many square inches are in a 3 in. bag of mulch?
A normal 2-cubic-foot bag will span 8-square feet with a depth of 3 inches. The relationship is linear; doubling the depth halving the coverage and vice versa.
Should I buy bagged or bulk mulch?
Price per cubic foot almost always wins when you do it by the bucket, and there won’t be any plastic waste, just a ton of dirt on your driveway and a lot of work using a wheelbarrow. Bags are easier to handle, can be put in a car and returned if you’ve gone overboard. Use both of these calculators to compare the actual difference with your prices.
Why are there various estimates for the same work from different suppliers?
Suppliers may round up to the nearest whole or half cubic yard and some will estimate slightly deeper to ensure you don’t run out. Ask what depth they modelled — and bring the number from this calculator.
Last updated: September ️13, 2026. Conversions follow the standard landscaping conventions (27 cu ft per cubic yard).
Disclaimer – Results are estimates for planning purposes. Actual mulch volume varies with settling, compaction, and supplier rounding. Always confirm volumes, prices, and delivery options directly with your supplier before purchasing.