Drainage Stone Explained: #5, #57, #67, and #78M
What the stone numbers mean, how the sizes differ, and which one fits drainage, backfill, and finish work.
June 5, 2026 · David Bowers · 1 min read
The numbers on crushed stone refer to a size grading, not a type of rock. Smaller numbers within a family are generally larger stone. Here is how the common drainage sizes compare and where each one shines.
#5 — around 1 inch
A larger, open stone that drains fast and resists clogging. Good for heavy drainage runs and as a general-purpose aggregate where you want plenty of void space.
#57 and #67 — about 3/4 inch
The workhorses. Both drain well and compact reasonably, which makes them go-to choices for driveways, pipe backfill, and concrete stone. #67 trends slightly smaller and tighter than #57.
#78M — about 3/8 inch
The smallest of this group. It locks together for a cleaner, finished surface and works well for decorative areas and fine drainage where you want less movement underfoot.
Quick picks
- Fast drainage or French drains: #5
- Driveways, backfill, all-purpose: #57 or #67
- Decorative or finish surface: #78M
Still deciding? The quote builder lists each size with its typical use and a delivered price, so you can compare before you order.