Stone calculator
Cobblestone Calculator
Cobbles are ordered by the piece or the pallet. Enter your area and cobble size for counts, base material and cost.
Your project
Crews typically order 5-10% extra to cover compaction, spillage and uneven subgrade.
Cobblestones needed
3,585
pieces
- Area
- 480 sq ft
- Cobbles per square foot
- 7.11
- Base stone (4" compacted)
- 7.11 cu yd
- Bedding sand (1")
- 1.48 cu yd
- Joint sand
- 10 bags (50 lb)
- Estimated cobble cost
- $8,963
Reclaimed granite setts vary in size by half an inch or more, which is part of the look. Order 10% extra and sort by size as you lay.
The shareable link reopens this calculator with your exact inputs.
Cobbles per square foot
With a 1/2 inch joint, 4" × 4" setts run about 6.4 per square foot, 4" × 7" about 3.8, 5" × 5" about 4.7, and 6" × 9" Belgian block about 2.2. Joint width matters more than people expect — widening from 1/4 to 3/4 inch cuts the piece count by roughly 10%.
Cobbles are often sold by the ton or the pallet rather than the piece. A ton of 4 inch granite setts covers about 25-30 square feet; a pallet is typically 1.5-2 tons.
Setting cobbles
Dry-laid: 4-6 inches of compacted base, 1 inch of coarse bedding sand, cobbles set with a mallet, then joints swept with polymeric sand and compacted. Driveways need 8 inches of base.
Mortar-set: a reinforced concrete slab, a bond coat, and mortared joints. This is the traditional method for historic streetscapes and the only way to stop cobbles migrating under turning truck traffic.
Cobbles per square foot (1/2" joints)
| Cobble size | Per sq ft | Per 100 sq ft |
|---|---|---|
| 3" × 3" | 10.4 | 1,040 |
| 4" × 4" | 6.4 | 640 |
| 4" × 7" | 3.8 | 380 |
| 5" × 5" | 4.7 | 470 |
| 6" × 9" | 2.2 | 220 |
Frequently asked questions
+How many cobblestones per square foot?
About 6.4 for 4" × 4" setts with 1/2 inch joints, 3.8 for 4" × 7", and 2.2 for 6" × 9" Belgian block.
+How much does a cobblestone driveway cost?
$25-$60 per square foot installed. Material alone is $10-$25 per square foot, and the labour is slow because every piece is set individually.
+What base do cobblestones need?
Four to six inches of compacted dense-graded base for walkways and patios, eight inches for driveways, plus one inch of coarse bedding sand.
+Do cobblestone joints need mortar?
Not for pedestrian areas — polymeric sand works well. Mortar joints over a concrete slab are worth it where vehicles turn and would otherwise shift the setts.