Gravel sizes by number
Crushed stone is sold by screen number: the stone passed one sieve and stayed on another. Lower numbers are bigger stone. This chart covers the sizes yards actually stock — pick the size, then head to the matching calculator for tons.
| Name / number | Stone size | Best for |
|---|---|---|
| Stone dust / screenings | < 3/16″ | Setting beds, path topping, joint sweep |
| Pea gravel | ⅜″ round | Walkways, playgrounds, between steppers |
| #8 | ⅜″ crushed | Pipe bedding, walks, chip-seal |
| #57 | ¾–1″ | Driveway top course, French drains, concrete mix |
| #4 | 1–2½″ | Heavy drainage, entrance stabilization |
| #3 | 1–2″ | Driveway base lifts, culvert surround |
| #2 | 2½–3″ | Construction entrances, soft-ground subbase |
| Crusher run / road base | fines–¾″ | Compacted base under everything |
| Rip-rap | 3–12″+ | Erosion control, banks, outfalls |
Which gravel size for which job?
The pattern behind the chart: fines compact, clean stone drains. Anything with dust in it (screenings, crusher run) locks into a hard mat — that's base and bedding. Anything washed (#8, #57, #3) stays open and moves water — that's drainage and top courses. Round stone (pea, river rock) is for feet and looks, never for structure. Once the size is settled, the gravel calculator turns area and depth into tons — or use the material's own page below.
Gravel size FAQ
What do gravel numbers like #57 mean?
They are screen sizes from the ASTM/AASHTO grading system — the number tells you which sieves the stone passed and stayed on. #57 passes a 1½ in screen and stays on a #4 (about ¾–1 in stone); the bigger the number, the smaller the stone.
What size gravel is best for a driveway?
Three lifts: big #3 stone (1–2 in) as the base where ground is soft, crusher run or road base as the middle, and 2–3 in of #57 (¾–1 in) on top. #57 is the classic driveway surface — big enough to stay put, small enough to walk and plow.
What size gravel for drainage?
Clean (washed, no fines) #57 is the all-purpose drainage stone for French drains and pipe bedding; step up to #3–#4 around perforated pipe under heavy flow. Never use anything with fines — the dust is what clogs fabric and pipe slots.
What size gravel for walkways?
Pea gravel (⅜ in, rounded) or #8 crushed for the surface — comfortable underfoot — over a compacted screenings or road-base layer so it doesn’t swallow shoes. Edge it; small round stone migrates.
What is crusher run?
Everything the crusher makes up to a top size — stone plus fines, usually ¾ in minus. The fines let it compact into a hard mat, which makes it a base material, not a drainage one. Regional names: CA-6, Class 5, 21A, dense-grade aggregate (DGA), road base.