Gravel Calculator | How Much Gravel Do I Need? m³ & Tons

How is gravel calculated?

Gravel quantity equals the fill volume. Volume = length × width × depth (or area × depth). Weight = volume × bulk density. Omni Calculator and site practice commonly use ≈ 1680 kg/m³ for standard gravel (~1.68 t/m³).

Steps

1. Enter length, width and gravel layer depth in meters (15 cm → 0.15).
2. If you know the area, use area × depth; if you know volume, enter m³ directly.
3. Pick standard, dry, wet or crushed density (or enter kg/m³).
4. Optionally add a ton, kg or m³ price.
5. Read required m³, tonnage and estimated cost.

Gravel densities (approx.)

Common guidance values for ordering and haulage:

How much area does 1 m³ of gravel cover?

The same volume covers different areas by layer thickness. Approx. for 1 m³:

Formula

Volume (m³) = length × width × depth. Weight (kg) = volume × density. Tons = kg ÷ 1000. 1 ton of gravel ≈ 1000 / density m³ (≈ 0.595 m³ at 1680 kg/m³). Example: 5 m × 1 m × 0.15 m = 0.75 m³ → 0.75 × 1680 = 1260 kg ≈ 1.26 t.

Practical tips

• Add about 5–10% for spread and waste; compacted fills may need 15–25% extra loose material.
• For tonnage orders, use the supplier bulk density—not solid rock specific gravity.
• 1 m³ standard gravel ≈ 1.68 t; 1 t ≈ 0.59–0.60 m³.
• Garden paths often use 5–10 cm; driveway base layers often 10–15 cm with a finer top course.

Field note

Results are guidance only. Moisture, grading and compaction vary by supplier and site.