Density Converter — kg/m³, g/cm³, lb/ft³ and More

Density is mass per unit volume — how heavy something is for its size. It determines whether objects float or sink, how much a container of material weighs, and whether a structure can support its load. If you work with materials, shipping, construction, or science, you convert density units regularly.

The CalcHub density converter handles all common density units.

Common Density Conversions

From	To	Multiply by
1 g/cm³	kg/m³	1,000
1 kg/m³	g/cm³	0.001
1 kg/m³	lb/ft³	0.06243
1 lb/ft³	kg/m³	16.018
1 g/mL	kg/m³	1,000
1 g/cm³	lb/ft³	62.43

Note: 1 g/cm³ = 1 g/mL = 1 kg/L = 1,000 kg/m³. These are all the same density expressed in different unit combinations.

Densities of Common Materials

Liquids

Material	Density (kg/m³)	Density (g/cm³)
Water (4°C)	1,000	1.000
Milk	1,030	1.030
Olive oil	910	0.910
Petrol/gasoline	750	0.750
Diesel	850	0.850
Mercury	13,546	13.546
Honey	1,420	1.420

Water at 4°C is the reference — its density of exactly 1 g/cm³ is by design (that's how the gram was originally defined).

Metals

Material	Density (kg/m³)	Density (g/cm³)
Aluminum	2,700	2.70
Steel	7,850	7.85
Copper	8,960	8.96
Gold	19,320	19.32
Titanium	4,507	4.51
Lead	11,340	11.34

Building Materials

Material	Density (kg/m³)
Concrete	2,300–2,500
Brick	1,600–2,000
Wood (pine)	500–600
Wood (oak)	600–900
Glass	2,500
Sand (dry)	1,500–1,700
Gravel	1,800–2,000

Practical Applications

Shipping and Logistics

Weight and volume both determine shipping costs. A 1 cubic meter box of feathers (density ~2.5 kg/m³) weighs almost nothing but takes up space. A 1 cubic meter box of steel (7,850 kg/m³) weighs nearly 8 tonnes. Shipping companies charge by "volumetric weight" or actual weight, whichever is higher.

Cooking

Recipes sometimes list ingredients by weight, sometimes by volume. Density is the bridge:

• 1 cup of flour ≈ 125g (density ~0.59 g/cm³)
• 1 cup of sugar ≈ 200g (density ~0.85 g/cm³)
• 1 cup of water = 237g (density ~1.0 g/cm³)

This is why "1 cup" of different ingredients weighs different amounts.

Construction

Structural engineers need to know how much a building material weighs per unit volume to calculate loads. A reinforced concrete slab at 2,400 kg/m³ that's 150mm thick exerts 360 kg per square meter — and every floor adds that load to the foundations.

Floating and Sinking

Anything less dense than water (1,000 kg/m³) floats. This is why:

• Ice floats (917 kg/m³) — which is critical for aquatic life in winter
• Oil floats on water (750–910 kg/m³) — which is why oil spills spread on the surface
• Steel ships float despite steel being 7,850 kg/m³ — because the hull encloses air, making the average density of the ship less than water

---

How does temperature affect density?

Most materials become less dense as they warm up (molecules move apart). Water is famously weird — it's densest at 4°C, not at 0°C. This is why ice forms on top of lakes, not the bottom.

What's the densest everyday material?

Lead (11,340 kg/m³) is the densest material most people encounter. Gold is denser (19,320 kg/m³) but less commonly handled. Osmium is the densest element at 22,590 kg/m³.

Why do scientists use g/cm³ while engineers use kg/m³?

Convention and convenience. At lab scale, g/cm³ gives numbers near 1 for common materials. At construction scale, kg/m³ gives whole numbers that are easier to work with (2,400 kg/m³ vs 2.4 g/cm³). They're just different expressions of the same measurement.

---

Related Converters

• Weight Converter — kilograms, pounds, ounces
• Volume Converter — liters, gallons, cubic meters
• Pressure Converter — pascals, PSI, atmospheres