Mulch Calculator
Free mulch calculator. Work out how many bags or bulk cubic meters of mulch your garden bed needs from area and depth, with bag-size presets, a bag versus bulk cost comparison and a coverage chart at common depths.
Loading tool...
What is Mulch Calculator?
The Mulch Calculator converts bed dimensions and a target depth into the volume of mulch you need, then into the number of standard bags or a bulk loose order rounded to a tenth of a cubic meter. It compares bag against bulk cost at your own prices, highlights the cheaper route, and includes a coverage chart at 5, 7.5, 10 and 15 centimeter depths so different beds can be planned in seconds.
Key Benefits
- Exact bag count for any bag size, rounded up so you never run short
- Bag versus bulk comparison with your own prices
- Coverage chart for planning several beds at different depths
- Works for bark, compost, straw or rubber mulch — anything sold by volume
- Copyable order summary for either buying route
Common Use Cases
- •Mulching flower borders and vegetable beds in spring
- •Ordering bulk bark chips for a large garden or playground
- •Topping up paths with a shallower layer than the beds
- •Estimating compost for a no-dig bed refresh
- •Comparing delivery versus car-boot bag hauling for an allotment
How to Calculate Mulch
- Measure the bed: Enter the length and width of the bed in meters. For odd shapes, measure the longest and widest points, or split the bed into rectangles and use the largest one.
- Pick the depth: Set the mulch depth: 5 to 7.5 centimeters for established beds, up to 10 centimeters for new beds and weed suppression, keeping it away from stems.
- Set the bag size: Enter the bag volume in liters from the packaging, commonly 30 to 60 liters. The calculator rounds the bag count up so you are never short.
- Compare bag and bulk: Enter your bag price and the bulk loose price per cubic meter. The cheaper option is highlighted, and the coverage chart shows bags needed at other depths.
Key Features
- Volume from bed length, width and depth in centimeters
- Bag count for any bag size in liters, rounded up
- Bag versus bulk cost comparison with a rounded bulk order
- Coverage chart at 5, 7.5, 10 and 15 centimeter depths
- Copyable shopping summary for either option