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Gravel Calculator

By Muhammad Abdullah Rauf · Founder, EverydayTools.proUpdated 2026-06-27

How much gravel do I need for a path or driveway?

Gravel volume is **area × depth**. For US paths and driveways, measure length and width in feet and compacted depth in inches.

**Imperial formula (rectangle):**

Cubic yards = Length (ft) × Width (ft) × Depth (in) ÷ **324**

Equivalently: Cubic feet = Length × Width × Depth (in) ÷ 12, then ÷ 27 for yards.

**Example — 10×40 ft walkway, 3 in gravel base:**

10 × 40 × 3 ÷ 324 = **3.70 cubic yards** (100 cu ft)

**Area-only mode:** Enter total square footage when your plan lists area — multiply area (sq ft) × depth (in) ÷ 12 for cubic feet.

**Coverage shortcut:** At 3 in depth, **1 cubic yard covers ~108 sq ft**. At 2 in, one yard covers ~162 sq ft. At 4 in driveway base, ~81 sq ft.

**Metric formula:**

Volume (m³) = Area (m²) × Depth (cm) ÷ 100

**Example — 30 m² path at 7 cm:**

30 × 0.07 = **2.1 m³** (2,100 liters)

Decorative gravel and crushed stone are sold **bulk by the cubic yard** or in **bagged cubic feet** at big-box stores. Add **5–15% extra** for compaction, edge spillage, and uneven subgrade. Compacted gravel occupies less volume than loose dump — suppliers often quote loose yards; compact on site.

Gravel volume formula

The calculator treats the paved zone as a flat rectangular prism (or known area × depth). An optional buffer increases order quantity for compaction loss and subgrade variation.

Formula

cu yd = L(ft) × W(ft) × D(in) ÷ 324  |  cu ft = area(sq ft) × D(in) ÷ 12  |  m³ = area(m²) × D(cm) ÷ 100

Assumptions

  • Gravel is spread to uniform depth over a flat, prepared subgrade.
  • Volume is loose material before compaction — not engineered aggregate spec sheets.
  • Irregular paths measured as total area are approximated as flat.

Limitations

  • Ton estimates use typical density ranges — confirm exact weight with your quarry for billing.
  • Does not model slopes, crown drainage, or geotextile underlayment.
  • Does not replace structural engineering for load-bearing driveways over soft soil.

How to use Gravel Calculator

  1. Choose your gravel use case

    Tap Decorative topping (2 in), Foot path (3 in), Patio base, Driveway base (4 in), or Side yard walk — each sets recommended depth with guidance.

  2. Measure path, pad, or round patio

    Enter length and width for rectangular paths and driveways, total area for curved walks, or diameter for round pads. Measure the paved footprint only.

  3. Read cubic yards and ton estimates

    Quarries quote crushed stone by the cubic yard or by the ton. Results show volume, estimated bulk weight, and ton rows for limestone, river rock, and granite.

  4. Check bag count on the main form

    Enter bag size (0.5 cu ft is common for decorative gravel) on the main form — bag count rounds up automatically. Leave blank to skip bags.

  5. Review bulk vs bag guidance

    The purchase guide recommends bulk delivery above ~2 cu yd and bagged retail for small accents — with gravel-specific tips.

  6. Add a compaction buffer

    Enable the buffer on the main form for driveways and heavily tamped bases. Ten percent is the default; use 10–15% for vehicle loads.

Gravel Calculator examples

10×40 ft path at 3 in (default)

Input

10 ft × 40 ft × 3 in

Output

100 cu ft · 3.70 cu yd

400 sq ft × 3 in ÷ 12 = 100 cu ft. ÷ 27 = 3.70 yards.

8×8 ft patio base at 3 in

Input

8 ft × 8 ft × 3 in

Output

16 cu ft · 0.59 cu yd

64 sq ft — borderline bulk vs bagged decorative gravel.

200 sq ft area at 4 in

Input

200 sq ft × 4 in

Output

66.7 cu ft · 2.47 cu yd

Heavier base depth for vehicle traffic or soft soil.

30 m² at 7 cm (metric)

Input

30 m² × 7 cm

Output

2.1 m³ · 2,100 L

30 × 0.07 m = 2.1 cubic meters of aggregate.

Who uses Gravel Calculator?

Common real-world scenarios where this tool saves time.

Side yard walkway

10×40 ft path at 3 in: 400 × 3 ÷ 12 = 100 cu ft → ~3.70 cu yd. Order 4 yards with buffer. Compact with a plate compactor between lifts if over 4 in total.

Patio base under pavers

12×12 ft pad at 3 in crushed stone: 144 × 3 ÷ 12 = 36 cu ft → ~1.33 cu yd. Add 1 in sand bedding separately — not included in gravel volume.

Driveway extension

12×20 ft strip at 4 in: 240 × 4 ÷ 12 = 80 cu ft → ~2.96 cu yd. Driveways often need 4–6 in #57 stone over geotextile — consult local codes.

Metric garden path

EU gardeners enter m² and cm for m³ output when buying bulk aggregate by the tonne — convert with supplier density separately.

Workflow guides

Step-by-step chains that connect related tools for common tasks.

Install a gravel garden path

From layout to delivery in four steps.

  1. Measure path length × width — default 3 in depth.
  2. Excavate, compact subgrade, install edging.
  3. Quote cubic yards from quarry or landscape yard.
  4. Convert volume if supplier quotes tonnes. Volume Converter

Reference tables

Coverage table — 1 cubic yard by depth

Square feet one loose cubic yard covers before compaction.

DepthSq ft per cu ydTypical use
2 in162Decorative topping · existing base
3 in108Foot paths · patio base (default)
4 in81Light driveway · heavy patio
6 in54Driveway base over soft soil

Formula: 324 ÷ depth (inches). Compaction reduces finished thickness — use buffer.

Gravel depth by application

ApplicationDepthStone typeNotes
Garden path2–3 inPea gravel · crushed finesEdging required
Patio base3–4 in#57 crushed stoneCompact before sand/pavers
Driveway base4–6 inCrusher run · #57Multiple lifts + compactor
Drainage swale6–12 inRiprap · large angularCheck local storm codes

Approximate weight per cubic yard

For tonnage quotes — varies by moisture and stone.

MaterialTons per cu yd (approx.)Notes
Crushed limestone1.3–1.5Common driveway base
Pea gravel1.2–1.4Rounded — shifts under load
River rock (decorative)1.1–1.3Lighter · larger voids
Lava rock0.8–1.0Very light — sold by cu ft at retail

Always confirm with your quarry — moisture changes weight.

Bulk vs bagged gravel

Volume neededBest formatTrade-off
Under 0.5 cu ydBagged retailHigher $/cu ft; easier for accents
0.5–2 cu ydBulk pickup or bagsTrailer load vs pallet
2+ cu ydBulk deliveryLowest $/cu yd; dump on tarp

Best practices

Excavate to firm subgrade

Use geotextile on clay

Match stone to use case

Common mistakes to avoid

Ordering decorative gravel at driveway depth

Pea gravel and river rock shift under tires. Driveways need **crushed angular stone** (#57, crusher run) at 4–6 in, not 3 in round rock.

Skipping compaction

Loose gravel settles. Plate-compact in 2–3 in lifts; order 10–15% extra or enable buffer.

Confusing tons and cubic yards

Suppliers may quote **tons**. Limestone ~1.4 tons/yd³, river rock less dense — ask conversion for your stone.

No edge restraint

Gravel migrates without edging or borders. Volume math does not include spill outside the footprint.

Measuring width including lawn

Measure only the **paved footprint** — not adjacent turf you will not cover.

Single thick lift over soft soil

Excavate soft topsoil, compact subgrade, geotextile if needed, then gravel in lifts.

Using mulch depth for gravel

Mulch is 2–4 in loose on soil. Gravel **bases** are 3–6 in compacted — different product and compaction.

Forgetting paver sand layer

Pavers need 1 in bedding sand **above** compacted gravel — calculate sand separately.

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Frequently Asked Questions

How much gravel do I need for a 10×40 foot path?

At 3 in depth (default): 400 sq ft × 3 ÷ 12 = 100 cu ft, or about 3.70 cubic yards. Round up to 4 yards with a compaction buffer.

How deep should gravel be for a walkway?

3 inches of compacted crushed stone or pea gravel is standard for foot traffic over a firm subgrade. Use edging to contain stone.

What is the formula for gravel in cubic yards?

For paths and pads: cubic yards = footprint length (ft) × width (ft) × gravel depth (in) ÷ 324. Area mode: (sq ft × depth in ÷ 12) ÷ 27. Order loose volume — compaction reduces finished depth.

How many tons of gravel in a cubic yard?

Depends on stone type. Crushed limestone is roughly 1.3–1.5 tons per cubic yard; river rock and pea gravel are slightly lighter. This calculator shows ton estimates for common stone types — confirm with your supplier for billing.

How much area does 1 cubic yard of gravel cover?

At 3 in depth, about 108 sq ft loose before compaction. At 4 in, about 81 sq ft.

Pea gravel vs crushed stone for driveways?

Crushed angular stone compacts and locks for vehicle loads. Pea gravel rolls and ruts — use it for paths, not driveways.

Should I compact gravel before calculating volume?

Calculate **loose** order volume, then add 10–15% buffer for compaction loss — enable the buffer on the main form for driveways.

Do I need landscape fabric under gravel?

Geotextile helps on clay and prevents sinking; it does not change volume math. Weed fabric alone does not support structural loads.

How much gravel for a 12×12 patio base?

At 3 in: 144 × 3 ÷ 12 = 36 cu ft (~1.33 cu yd). Add separate sand layer for pavers.

Can I use the mulch calculator for gravel?

Volume math is identical, but depth recommendations and compaction differ. Use this Gravel Calculator for path and driveway defaults.

Privacy, accuracy, and trust

Privacy

Path and driveway measurements stay on your machine only — EverydayTools never uploads gravel project dimensions or depth settings to external servers.

Volume estimates only — not civil engineering, structural pavement design, or commercial estimating. Confirm stone spec and quantities with your supplier.

Part of Calculator Tools

More free tools for the same workflow.

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Reviewed on 2026-06-27.