How many pavers do I need?

Divide the patio area by the face area of one paver, then add for cuts. A 200 ft² patio with 8 × 4 in pavers needs 200 ÷ 0.222 = about 900 pavers before waste, so order roughly 990. Order the cuts from the same batch — colour varies between production runs.

For a residential patio, 4 inches of compacted aggregate is the usual figure. A driveway carrying vehicles takes more, commonly 8 inches or more, and soft or clay subgrade takes more again. The base does the structural work, so this is the layer to be generous with.

About 1 inch, screeded flat and left uncompacted before the pavers are set. Deeper bedding is the most common cause of a patio that settles into ruts a year later, because sand consolidates under load in a way a compacted aggregate base does not.

That is a separate material for the joints between pavers after they are laid. It is sold by the bag with coverage quoted per square foot, and how far a bag goes depends on joint width and paver depth, so take the figure from the bag rather than assuming.