Gravel Calculator - 無料オンライン電卓

Gravel calculation is essential for any Indian home or commercial project involving driveways, courtyards, walkways, French drains for monsoon water management, pebble landscaping around plants, foundation backfill, basement drainage layers, or aggregate for RCC concrete work. Indian construction uses a wide variety: 6mm and 12mm aggregate (gitti) for concrete, 20mm and 40mm for road base and PCC, river-rounded pebbles for decorative pathways and Zen gardens, crushed black trap stone in Western India, granite chips in Southern India, and limestone gravel where available. Pricing varies dramatically by region - a brass (100 cu ft) of 20mm aggregate ranges from ₹3,000 in tier-3 cities to ₹6,000+ in metros, and supply is bought either by tipper truckloads or by brass.

This calculator converts your project area and target depth into the volume of gravel needed, plus weight in US tons and metric tonnes (which is how truckload deliveries get billed). The standard density assumption is 95 lb per cubic foot (1500 kg/m³) which suits most common landscape and construction gravel - pea gravel is slightly lighter (~85 lb/cu ft) and dense crushed stone like black trap is heavier (~100-105 lb/cu ft). Add 10-15% buffer for compaction, especially for driveways and base layers where the gravel gets pressed down under traffic and weather. For Indian use, also convert cubic feet to 'brass' (100 cu ft) which is the most common Indian sale unit.

Volume = area × depth, all units consistent. Area in square feet × depth in feet = volume in cubic feet. For depth specified in inches, divide by 12 first. Example: 200 sq ft driveway at 4 inch base depth = 200 × 4/12 = 66.7 cu ft = 2.47 cu yd. Always plan in cubic feet first, then convert.

Indian unit conversions: 1 brass = 100 cu ft = 3.7 cu yd. 1 cu m = 35.3 cu ft. 1 cu yd = 0.765 cu m. Truckload (tipper) capacity varies by truck size: small tipper ~100 cu ft (1 brass), large tipper 200-300 cu ft (2-3 brass). When you order, sellers quote per brass or per tipper. Knowing the exact volume you need lets you negotiate the right truckload count instead of being upsold.

Weight calculation: cu ft × 95 lb/cu ft = pounds, then divide by 2000 for US tons or by 2204.62 for metric tonnes. Useful when buying by weight (some industrial sellers price gravel by metric tonne). For density of specific Indian aggregates: granite chips ~1600 kg/m³, basalt/black trap ~1700 kg/m³, river pebbles ~1500 kg/m³, sand-mixed gravel ~1650 kg/m³.

Depth recommendations: driveways need 4-6 inches total (2 inches compacted base + 2 inches surface, both compacted by traffic). Walkways and patios 2-3 inches. French drains 6-12 inches (with perforated pipe at base). Decorative pebble layers 1-2 inches. Foundation drainage 4-6 inches. Always add 10-15% buffer for compaction and spillage.