Density Calculator
A professional-grade density calculator for scientists, engineers, students, and logistics teams. Compute density, mass, or volume with consistent units, convert results instantly, and even estimate LTL freight class from package dimensions.
Interactive Calculator
You can still choose any unit below.
Mass is the quantity of matter. Use the object’s weight converted to mass if necessary. For everyday use on Earth, weight in pounds approximates mass in lb.
Volume is the space an object occupies. If you have dimensions, switch to Box or Cylinder to compute it automatically.
Density varies with temperature and pressure. Use values appropriate to your conditions (e.g., water ≈ 1000 kg/m³ at 4°C).
Select a material to prefill density. You can edit the value afterwards.
Freight density helper (LTL) — optional
Freight density: —
Results
Density
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SI density (kg/m³)
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g/cm³ (g/mL)
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lb/ft³
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lb/in³
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lb/gal (US)
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Data Source and Methodology
Authoritative data on units and symbols are taken from:
International Bureau of Weights and Measures (BIPM), The International System of Units (SI), 9th edition, 2019.
Direct link (PDF).
Tutti i calcoli si basano rigorosamente sulle formule e sui dati forniti da questa fonte.
Methodology: all inputs are converted to SI base units (kg and m³) internally. Calculations use the canonical physics relationship ρ = m / V, with inverse forms for solving mass or volume. Results are then converted to the requested output units without loss of precision beyond floating-point rounding.
The Formula Explained
Density: $$\\rho = \\frac{m}{V}$$
Mass from density and volume: $$m = \\rho\\,V$$
Volume from mass and density: $$V = \\frac{m}{\\rho}$$
Box volume: $$V_{box} = L\\,W\\,H$$
Cylinder volume: $$V_{cyl} = \\pi\\,\\left(\\tfrac{d}{2}\\right)^2 h$$
Freight density (US customary): $$\\rho_{freight}\\,[\\tfrac{lb}{ft^3}] = \\frac{W_{lb}}{\\tfrac{L_{in}\\,W_{in}\\,H_{in}}{1728}}$$
Glossary of Variables
- ρ (Density): amount of mass per unit volume. Units: kg/m³, g/cm³, g/mL, lb/ft³, lb/in³, lb/gal.
- m (Mass): quantity of matter. Units: kg, g, lb, oz.
- V (Volume): 3D space occupied. Units: m³, L, mL, cm³, ft³, in³, US gal.
- L, W, H: length, width, height for box shapes (m, cm, mm, ft, in).
- d, h: diameter and height for cylinders (m, cm, mm, ft, in).
- Freight class: estimated NMFC class derived from density ranges; confirm with your carrier.
How It Works: A Step-by-Step Example
Suppose you have 0.5 kg of liquid occupying 0.5 L. Convert 0.5 L to m³: 0.5 L = 0.0005 m³. Apply the formula:
$$\\rho = \\frac{m}{V} = \\frac{0.5\\;kg}{0.0005\\;m^3} = 1000\\;kg/m^3$$
Conversions: 1000 kg/m³ = 1 g/cm³ = 1 g/mL ≈ 62.42796 lb/ft³ ≈ 8.3454 lb/gal. The calculator performs these conversions automatically.
Frequently Asked Questions (FAQ)
Is density the same as specific gravity?
No. Specific gravity is the ratio of a substance’s density to a reference (often water at 4°C). It is dimensionless, while density has units.
Can I compute mass if I only know dimensions and density?
Yes. Use Box or Cylinder to compute volume, then choose “Mass (m)” as the solve-for option. The tool will do m = ρ·V for you.
Which water density should I use?
At 4°C, water is about 1000 kg/m³ (1 g/cm³). At 20°C it’s ≈ 998.2 kg/m³. Select a value appropriate to your temperature.
Why do I get very small numbers in lb/in³?
Because a cubic inch is a very small volume. Use lb/ft³ or lb/gal for more familiar scales in US customary units.
What precision does the calculator use?
Internally it uses double-precision floating point. Results are displayed with sensible rounding; you can copy the SI value for maximum precision.
Is the freight class accurate?
It’s an estimate using common density thresholds. Actual NMFC class also depends on handling, liability, and stowability—confirm with your carrier.
Strumento sviluppato da Ugo Candido,. Contenuti verificati da,.
Ultima revisione per l'accuratezza in data: September 15, 2025.
Ultima revisione per l'accuratezza in data: September 15, 2025.