Density is mass per unit volume — how much material is packed into a given space. Water has a density of 1 g/cm³ or 1,000 kg/m³. Denser materials (like iron at 7.87 g/cm³) are heavier for the same volume; less dense materials (like foam) are lighter.

Why is density important in freight?

Freight density determines shipping class and cost. Carriers categorize cargo by density (lb/ft³). Low-density cargo takes up space but is light; high-density cargo is heavy and compact. Density affects both freight class and dimensional weight calculations.

What units does this calculator support?

Density: kg/m³, g/cm³, lb/ft³. Mass: kg, g, lb, oz. Volume: m³, cm³, L (liters), ft³ (cubic feet). The calculator automatically converts between all standard units.

What's the difference between mass and weight?

Mass is the amount of material (kg, g, lb, oz). Weight is mass × gravity and varies by location. On Earth's surface, we often treat them as equivalent. This calculator works with mass; weight is gravity-dependent.

Density Calculator

Q: How do I calculate density?

Density = Mass ÷ Volume. Measure or know the mass and volume of the object, then divide. Make sure units are consistent. This calculator handles unit conversions automatically.

Q: How do I convert between density units?

1 g/cm³ = 1,000 kg/m³ ≈ 62.43 lb/ft³. Water at 1 g/cm³ is the reference standard. This calculator performs all conversions automatically.

Calculate density, mass, or volume using the density formula. Choose your mode and enter known values. Supports kg/m³, g/cm³, lb/ft³ for density and multiple units for mass and volume. Ideal for material procurement, freight classification, and packaging decisions.

Solve the density formula for any unknown. Choose a mode (Find Density, Find Mass, or Find Volume), enter the known values, and calculate. Supports multiple units for density, mass, and volume.

Freight classificationMaterial procurementPackaging decisionsQuality control

Mode

Mass

Volume

Formula

Density = Mass ÷ Volume | Mass = Density × Volume | Volume = Mass ÷ Density

The density formula relates mass, volume, and density. Rearrange to solve for any unknown. Common density units: kg/m³ (metric), g/cm³ (material science), lb/ft³ (imperial). This calculator converts between all standard units automatically.

Frequently Asked Questions

Use this in your workflow

Use the Volume Calculator to find volume, then use density to find mass. For freight decisions, pair with the Freight Density Calculator. Browse all Free Calculators.

When to use this calculator

→Determining freight classification or density-based shipping rates
→Material procurement where density affects weight or volume decisions
→Packaging optimization to balance weight limits with space constraints
→Quality control or product verification using density as an indicator

Worked example: freight classification

A typical logistics scenario.

Item	Value
Package mass	500 kg
Package volume	2.5 m³
Calculated density	200 kg/m³
Freight class threshold	15 lb/ft³ ≈ 240 kg/m³
Freight classification	Class 50 (density below threshold)

At 200 kg/m³ (12.5 lb/ft³), this cargo is classified as "low density" freight, requiring more space relative to weight. Freight rates would reflect the need for cube space, potentially making dimensional weight a factor in pricing.

Limitations

This calculator assumes uniform density throughout the material and uses standard gravity conversion factors. Real-world materials may have variable density. Temperature and pressure affect density (especially for gases and liquids). For precision applications, consult material specifications or technical data sheets. Results are for planning purposes — verify with actual measurements or material properties for critical decisions.

Related calculators

Volume CalculatorCalculate volume for 3D shapes Weight CalculatorConvert weight and mass units Freight DensityCalculate freight density for class Freight ClassDetermine freight class from density

Frequently asked questions

What is density?

Density is mass per unit volume — how much material is packed into a space. Water has a density of 1 g/cm³. Iron is denser at 7.87 g/cm³ (heavier for the same volume). Foam is less dense, lighter for the same volume.

How do I calculate density?

Density = Mass ÷ Volume. If you know mass and volume, divide them. Make sure units are consistent; this calculator converts automatically between all standard units.

Why does freight density matter?

Freight carriers classify cargo by density. Low-density cargo (light for its size) is classified higher (e.g., Class 50) and costs more per pound. High-density cargo (heavy for its size) is classified lower (e.g., Class 55+) and may cost less per pound.

What are common density values?

Water: 1 g/cm³. Ice: 0.92 g/cm³. Wood: 0.5–0.9 g/cm³. Iron: 7.87 g/cm³. Steel: 7.75 g/cm³. Aluminum: 2.70 g/cm³. Air: 0.0012 g/cm³. Use these as references.

How do I convert between density units?

1 g/cm³ = 1,000 kg/m³ ≈ 62.43 lb/ft³. Water (1 g/cm³) is the reference. This calculator automatically converts between all common units.

Can density change?

Yes. Density changes with temperature (especially for liquids and gases). Pressure also affects density. For solids at room temperature and standard pressure, density is relatively stable. Always verify with material specs if precision is critical.