# Density Calculator (ρ = m/V) Compute density, mass, or volume from the other two, with specific gravity and a float/sink check > Canonical page: https://elysiatools.com/en/tools/density-calculator - **Category:** Math & Numbers - **Keywords:** density, mass, volume, rho, specific gravity, relative density, buoyancy, physics, ρ=m/v, float sink ## Overview Density relates mass and volume. Equations (three-way solver): - Density: ρ = m / V - Mass: m = ρ · V - Volume: V = m / ρ Specific gravity = ρ / ρ_water (ρ_water = 1000 kg/m³). SG < 1 floats, SG > 1 sinks. ## Inputs - **Solve For** (select) - **Density (ρ, kg/m³)** (number): leave blank when solving for density - **Mass (m, kg)** (number): leave blank when solving for mass - **Volume (V, m³)** (number): leave blank when solving for volume ## When to use - When you need to calculate the density of a material given its mass and volume. - When you need to determine the total mass of a substance based on its volume and known density. - When you want to evaluate if an object will float or sink in water by checking its specific gravity. ## How it works - Select the target variable you want to solve for: Density (ρ), Mass (m), or Volume (V). - Enter the two known values in their respective fields using standard units (density in kg/m³, mass in kg, or volume in m³). - The calculator computes the missing value using the formula ρ = m/V, calculates the specific gravity relative to water, and displays whether the object floats or sinks. ## Use cases - Physics students solving homework problems involving density, mass, and volume relationships. - Engineers calculating the weight of a structural component based on its material density and volume. - Logistics planners estimating the volume occupied by a cargo shipment of a known mass and density. ## Frequently asked questions ### What units are used for the calculations? Mass is measured in kilograms (kg), volume in cubic meters (m³), and density in kilograms per cubic meter (kg/m³). ### How is specific gravity calculated? Specific gravity is calculated by dividing the substance's density by the density of water (1000 kg/m³). ### How does the calculator determine if an object floats or sinks? If the calculated specific gravity is less than 1, the object floats; if it is greater than 1, the object sinks. ### Can I calculate the volume if I only know the mass? No, you must provide two of the three variables (density, mass, or volume) to solve for the third. ### What is the density of water used in this calculator? 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