Yards and tons answer different questions about the same pile. A yard is a volume, three feet each way, and it is what you calculate from the area and depth you measured. A ton is a weight, and it is what the supplier charges for. Getting from one to the other needs the density of the specific material, which is why the honest answer to how many tons are in a yard always starts with which material and how wet it is.
Calculating yards of gravel: start with the volume you actually measured
Area multiplied by depth, with the depth converted to the same unit, then divided by twenty seven to get cubic yards from cubic feet. That number is a fact about your site and does not change with supplier or material, which is why it is worth writing on the estimate.
How many yards of sand in a ton? Use the supplier's figure, not a generic one
Ask your supplier what a yard of the material weighs and use that. The general range for dry aggregate is well known and the specific number is what gets delivered. Sand is usually heavier per yard than coarse aggregate, and a wet load is heavier than a dry one, sometimes noticeably.
Sanity check the answer against the truck
Knowing roughly what a delivery vehicle carries turns an abstract number into a decision: whether this is one load or two, and whether a second delivery charge is in the price. A yard of gravel is a substantial pile, and a customer who has never seen one will be surprised by what arrives.
Questions people ask about how many yards of gravel do i need
How big is a yard of gravel?
A cubic yard is three feet by three feet by three feet, twenty seven cubic feet. Spread four inches deep it covers roughly eighty square feet, which is the comparison most people find useful when they are staring at a driveway.
Should I order in yards or tons?
Order in whatever your supplier prices in, and do the conversion yourself so you know what is arriving. Quoting the customer in one unit and ordering in another is how a job ends up short by exactly the conversion error.
Does moisture really matter?
For weight, yes: a wet load can be noticeably heavier than the same volume dry, which matters when you are buying by the ton and spreading by the yard. It is another reason to take the conversion figure from the supplier on the day.