Basketball Court Calculator
— How Much Do You Need?

A basketball court is only as good as what's underneath it, and Hello Gravel supplies the foundation that makes the whole thing work. Most court builds call for two types of aggregate: a sub-base layer for drainage and a compacted base layer for structural stability. The sub-base is typically coarse crushed stone, such as #57 stone, laid at a depth of 4 to 6 inches. This layer lets water filter through rather than pool underneath your court. On top of that, a base course of crusher run or dense-graded gravel is compacted to 2 to 4 inches of finished depth. This upper layer binds tightly when compacted, giving you a firm, load-bearing platform that your finished court surface can be installed on. Hello Gravel can deliver both materials in bulk so you have everything on site and ready to go.

For the base course layer, crusher run is the most widely recommended aggregate for a basketball court. Depending on your region, you may also hear it called dense-graded aggregate, road base, or processed gravel. It is a blend of crushed stone and stone dust, and when it is compacted, the finer particles fill in the voids between the larger pieces and lock everything together. The result is a dense, stable layer that resists shifting, supports weight evenly, and holds its shape over time. For the sub-base layer beneath the crusher run, #57 crushed stone is a strong choice. Its open, angular structure allows water to drain through freely, which protects your base from frost heave and erosion during wet or cold seasons. Using the right material in each layer is what separates a court that stays flat for years from one that cracks or settles prematurely. If you are not sure which grade makes the most sense for your specific region or soil conditions, the Hello Gravel team can help point you in the right direction before you order.

Yes, and the reason comes down to the fact that each layer does a completely different job. The sub-base at the bottom is built for drainage. Water that works its way under your court needs somewhere to go. Coarse, open-graded stone like #57 gives it a clear path to drain away rather than sitting trapped beneath the surface. In colder climates, trapped moisture freezes, expands, and can heave or crack your court surface from below. Proper drainage at the sub-base level prevents this. The base course on top of the sub-base is built for load-bearing and stability. Materials like crusher run compact into a dense, rigid layer that distributes weight evenly across the surface and gives your paving or court tile contractor a flat, consistent platform to work on. Skipping either layer is a common shortcut that tends to show up as drainage problems, uneven settling, or surface cracking within a few seasons. Building the base right the first time is almost always less expensive than fixing it after the surface is installed.

The right quantity depends on your court's dimensions and the depth of each base layer. To give you a sense of scale, a regulation high school court measures 84 by 50 feet, which is 4,200 square feet. A common residential half court runs about 30 by 50 feet, or 1,500 square feet. For a combined base of 4 inches of sub-base and 4 inches of base course, you would be working with roughly 8 inches of total material depth across both layers. At that depth, a 30 by 50 foot half court would require approximately 37 to 40 tons of aggregate across both layers. A full 84 by 50 foot high school court at the same depth would require approximately 105 to 115 tons. These are real-world estimates based on standard compaction rates, but your actual number will vary depending on your soil conditions, how much grading your site needs, and whether you are compacting in stages. The Hello Gravel online calculator is the best tool to get a precise figure for your specific court dimensions and target depth. It only takes a few minutes and takes the guesswork out of ordering.

Site preparation is where the success of your basketball court is actually decided, and it all happens before your first ton of aggregate arrives. Start by staking out the full footprint of your court, plus a few extra feet around the perimeter to give yourself clean edges to work with. Then excavate the area to a depth that accommodates your sub-base, base course, and intended surface combined. For most builds, that means digging down 8 to 12 inches below the final finished grade. Once the area is excavated, compact the native soil at the bottom of the excavation using a plate compactor or vibratory roller. Any soft, wet, or unstable spots in the subgrade need to be addressed at this stage before you start building up. If your site has significant low areas that need to be built up before the stone layers go down, Hello Gravel carries fill dirt that can help you establish a consistent grade across the footprint. Getting this foundation step right before the aggregate arrives makes everything that follows faster and more predictable.