How it is worked out
Each paver covers its own size plus one gap along and one across. The area divided by that gives the count, rounded up, and the extra is added on top.
Bedding sand is the area × the sand depth. Depth is entered in millimetres and divided by 1,000.
The base under the sand is separate. For that, use the mulch and soil calculator with your base depth.
Worked example
The numbers this page opens with: length 5 m, width 3 m, paver length 200 mm, paver width 100 mm, gap between pavers 3 mm, extra for cuts and breakages 5 %, bedding sand depth 30 mm.
The answer: area 15.00 m²; pavers per square metre 47.8 pavers; pavers, exact 718 pavers; pavers with 5% extra 754 pavers; bedding sand at 30 mm 0.45 m³.
Questions
Do I order pavers by number or by square metre?
Suppliers usually quote per square metre and deliver by the pallet. Take the area and the count, and ask how many are on a pallet.
Does it include edge restraints or jointing sand?
No. Edging runs the length of each open side, so measure those sides in lineal metres.