Construction & materials tools

Gravel Calculator

Estimate how much gravel you need in cubic yards or cubic metres for one or more rectangular areas, with an optional density-aware result in short tons or metric tonnes.

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Transparent MathBuilt on visible volume formulas.
CustomizableEditable waste % and bulk density.
Multiple AreasAdd unlimited rectangular sections.
Instant ResultsLive volume & weight conversion.

Add each rectangular area. The suggested 10% waste value is editable and is not a universal recommendation.

How to measure a gravel project

Measure length and width for each rectangular section in feet or metres, then choose the planned compacted depth. Add multiple rectangular areas if your project has sections with different shapes or depths.

Read the complete measuring guide

GUIDE01

How much gravel do I need?

Measure each area's length and width, then choose a representative compacted depth. Add separate areas when the dimensions differ.

Read the measuring guide

METHOD02

Why weight is an estimate

Bulk density changes with rock type, gradation, moisture, voids, and compaction. Weight appears only after you choose a documented source reference or enter a custom positive density.

Learn about our assumptions

AREAS03

Multiple project areas

Add driveways, patios, and paths as separate areas. Totals combine volume and estimated weight for all areas.

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Formula

Volume = length × width × depth

Order volume = total raw volume × (1 + waste % ÷ 100)

Step-by-Step Scenario

Worked example: Driveway & Patio Base

12 ft × 12 ft × 3 in Pad

A 12 ft × 12 ft gravel pad excavated to 3 in deep (0.25 ft) has a net volume of 36 ft³ (1.3333 yd³). With a recommended 10% compaction & spreading allowance, the total order volume is 1.4667 yd³.

Length

12 ft

3.66 m

Width

12 ft

3.66 m

Depth

3 in

0.25 ft / 7.6 cm

Order Volume

1.4667 yd³

+10% buffer

Formula Calculation

1. Net Volume:12 ft × 12 ft × 0.25 ft = 36 ft³ (1.3333 yd³)

2. +10% Allowance:36 × 1.10 = 39.6 ft³ (1.4667 yd³)

Practical Conversions

Real-World Equivalents

How 1.4667 yd³ translates into standard gravel supplier units:

Estimated Weight

at 2,800 lb/yd³ (crushed rock)

≈ 2.05 tons 4,107 lbs

Standard 50 lb Bags

Retail bagged stone

≈ 82 bags (50 lbs each)

Metric Volume

Standard cubic meters

≈ 1.12 m³ bulk gravel

Orders exceeding 2 tons are usually most economically delivered by a quarry dump truck rather than retail bags.

Before ordering gravel

The gravel estimator first calculates volume from length, width, and depth. Use cubic yards or cubic metres when buying by volume; when a supplier quotes by weight, the density-aware conversion provides the corresponding short-ton or metric-tonne estimate.

Confirm the measured area and compacted depth.
Ask whether the supplier sells by volume, short ton, or metric tonne.
Use a density for the actual gravel product, moisture, and compaction state.
Choose a project-specific allowance for compaction, spillage, and irregular edges.

For construction and maintenance context, see the FHWA Gravel Roads Construction and Maintenance Guide. Verify the final quantity and delivery constraints with your supplier.

HELP & GUIDELINES