How much sand under pavers?
Pavers sit on a 1-inch layer of washed concrete sand, screeded flat over the compacted base. More than that lets the pavers rut and settle. Area x 1/12 ft gives the cubic feet; at about 100 lb per cubic foot, 200 sq ft of patio needs about 18 cu ft (with 10% extra) — just under a ton, or 37 bags of 50 lb.
Polymeric jointing sand
After the pavers are laid and compacted, polymeric sand is swept into the joints and misted so it hardens. A 50 lb bag covers roughly 60–100 sq ft of tight-jointed pavers and 30–60 sq ft with wide joints or tumbled stone. The calculator uses the middle of each range; the bag's chart for your paver is the final word.
What not to use
Skip stone dust and play sand for the bedding layer — they hold water and pump out from under the pavers. Polymeric sand goes only in the joints, never as bedding.
Planning the whole patio? The paver calculator works out pavers, base, sand and edging together.