Step 1: Calculate the area of your sandbox
For square and rectangular sandboxes, that means length x width. If your sandbox is new, you should be able to find this information on the packaging somewhere. If not, be sure to measure the interior of your sandbox when you’re taking measurements.
So if your sandbox is 5’ x 5’, you’ll have 25 square feet to fill with sand.
Step 2: Decide how deep you want the sand to be
First, you’ll need to know how tall your sandbox is. From there, you can decide how deep you’ll want the sand to be. It’s usually a good idea to leave a few inches of space at the top. Filling your sandbox to the brim can make it tough to put on protective covers – not to mention, it will be hard for your kiddos to even get in their sandbox!
So, let’s say your 5’ x 5’ sandbox is 8” deep. We recommend 4-6” of sand.
Step 3: Calculate the volume of sand you need
Ready to make your high school geometry teacher proud? Play sand is usually sold in bags that measure it by the cubic foot. In other words, you need to know the volume of sand you need to make your purchase.
For square and rectangular sandboxes, this is your area (the measurement from step 1) multiplied by the height you want your sand to reach. Or to put it simply, length x width x height.
Remember that you need all your measurements to be in feet. So if you’re measuring the height of your sand in inches, divide that number by 12 to get your height in feet. For example, 6” is equivalent to 0.5’.
So, if you want 6 inches of sand in your 5’ x 5’ x 8” sandbox, you’ll multiply 5’ x 5’ x 0.5’ to find how many cubic feet of sand you need. In this case, it’s about 12.5 cubic feet!
Step 4: Determine how many bags of sand you’ll need
Play sand is usually sold in 50 lb bags that contain approximately ½ cubic feet of sand. So to figure out exactly how many bags you’ll need, take your volume measurement from step 3 and multiply it by 2.
So to get the 12.5 cubic feet of sand we’ll need for our 5’ x 5’ sandbox, we’ll need to buy about 25 bags of play sand!
What about circular sandboxes?
All of the steps above apply to circular sandboxes as well. You’ll just use a different formula to calculate the area and volume. Of course, if you can find that information on the packaging, that’s your easiest option!
If not, you’ll need to measure the diameter of the circle yourself. Then, divide that number by 2 to get the radius. To calculate the area of the circle, multiply the radius by itself and then by π (3.14). So for a circle, area = pi x radius x radius or A = πr2
With the area calculated, you can follow steps 2 - 4 as normal. Simply multiply the area of the circle by the height of sand you want (in feet) to calculate how many cubic feet of sand you’ll need.
Shop KidKraft Sandboxes
Of course, before you buy the sand, you’ll need the perfect sandbox! Our large wooden sandboxes are sturdy, sleek, and ready for playtime!