Gravel for a 20×20 Area at 4" Deep
Covering a 20×20 area 4 inches deep takes about 6.7 tons of gravel (4.94 cubic yards). Change the size or depth below — driveways usually run 4–6".
Gravel needed
6.7 tons
Area
400 sq ftat 4" deep
Gravel needed
6.7 tons4.94 cubic yards
Delivered cost (est.)
$300~$45/ton crushed gravel
Doing this for work? Estimate the whole job in minutes.
JRIQ turns plans and site photos into full material + labor estimates with AI — built by the team behind these calculators.
Try it free →
How this is calculated
Mulch volume = bed area × depth. We convert cubic feet to cubic yards for bulk delivery and to 2-cu-ft bags for the bagged option, so you can compare cost both ways.