Mulch calculator
Estimate mulch volume, whole bags to buy, and bag costs for a rectangular landscape area.
Mulch calculator
Estimate landscape volume and whole bags to buy.
Material estimate only. Confirm pack sizes, minimum orders, local prices, and project requirements before buying. Prices exclude delivery and taxes.
How to use the mulch calculator
- Choose metric or imperial units. Measure the length and width of a rectangular bed and enter the intended mulch depth in centimetres or inches.
- Adjust the extra allowance and enter the actual bag volume from the packaging: litres in metric mode or cubic feet in imperial mode.
- If you want a bag-cost estimate, choose the supplier’s currency and enter the price of one bag.
- Click Calculate mulch. Review the total volume and rounded-up number of bags. For several beds, combine their required volumes before deciding how many bags to buy.
Frequently asked questions
Practical answers for this calculator. Select a question to read more.
How deep should I spread the mulch?
The sample 5 cm depth is not a recommendation for every plant or material. Appropriate depth depends on the mulch type, planting, drainage, and existing mulch. Follow relevant product or local horticultural guidance, and enter only the additional depth you intend to apply.
What if my mulch bags are sold by weight?
This calculator needs bag volume, not bag weight. A 20 kg bag is not necessarily 20 litres because materials have different densities and moisture contents. Ask the supplier for the bag’s volume rather than treating kilograms as litres.
Why is the bag count rounded up?
You normally cannot buy a fraction of a sealed bag. For example, 660 litres divided by 40 litres per bag is 16.5 bags, so the tool reports 17. The optional bag cost uses that rounded-up count.
Can I use the result to order bulk mulch?
Yes, use the displayed volume with allowance and confirm the supplier’s volume unit and minimum order. The cost field is specifically price per bag; it is not a bulk-price field. Calculate a bulk quote from the supplier’s matching unit price separately.
How should I measure an L-shaped or irregular bed?
Split an L-shaped bed into non-overlapping rectangles, calculate each volume, and add the volumes. For a combined bag purchase, divide the combined volume by bag volume and round up once. Curved beds need an area estimate or a shape-specific method; this tool does not calculate curves exactly.
For more detail, read our methodology and disclaimer. Found a problem? Contact CalHomeGo.
Calculations run in your browser. Optional currency conversion contacts Frankfurter for rates; your measurements and cost amounts are not sent. Reference rates are not bank quotes.