Mulch Calculator
Mulch Calculator
Calculate yards and bags for your garden
Planning a landscaping project is a great way to boost your home’s curb appeal. But let’s be honest here. Hauling fifty bags of mulch from the store only to find out you are ten bags short is a total nightmare. This mulch calculator gives you the exact volume you need based on your garden bed size. In 2026, premium hardwood mulch usually costs between $3 and $7 per bag. Using this tool ensures you buy exactly what you need without making three extra trips to the garden center. You’ll get the cubic yards for bulk delivery and the bag count for retail pickup in seconds.
How to use this mulch calculator
- Measure your beds: Get the total length and width of the garden area in feet.
- Choose your depth: 3 inches is the gold standard for weed control and moisture retention.
- Check the buffer: Our tool adds 10% for settling. Mulch decomposes and packs down over time so you need that extra bit.
- Calculate: The tool shows you the bulk yards and the number of 2-cubic-foot bags to buy.
The Mulch Math Formula
Our mulch calculator uses the standard volume formula to ensure you don’t under-buy. First, we multiply the length by the width. Then we multiply that by the depth in feet. Finally, we divide by 27 to get the cubic yards.
If you are buying bags, we divide the total cubic feet by 2. This is the size of a standard mulch bag at most hardware stores. We always round up to the nearest whole bag. It is much better to have one extra bag for thin spots than to leave your soil exposed to the sun. Having a little extra also helps when you need to top off areas after a heavy rain.
Why 3 Inches is the Magic Number
I see many homeowners try to save money by spreading mulch only 1 inch thick. This is a waste of time. A thin layer doesn’t stop weeds. It won’t hold moisture either. You need at least 3 inches of mulch to properly insulate your plant roots. However, you shouldn’t go deeper than 4 inches. If you do, you might suffocate your plants. Stick to the 3-inch rule for the best results and a professional look.
