The Specific Gravity to Density Calculator turns a substance’s specific gravity into its density. Specific gravity tells you how heavy something is compared to water, and density measures how much mass fits in a certain space—like kilograms per cubic meter. This tool falls under the category of science calculators, making it perfect for students, engineers, or anyone working with materials—like in labs, construction, or even cooking.
Why is this helpful? Knowing density helps you understand how substances behave—like if they’ll float or sink, or how much space they take up. This calculator makes it quick by using specific gravity and a reference value (usually water’s density) to give you the answer. It’s great for real-life decisions, like choosing materials, mixing liquids, or checking product quality. Plus, it’s reliable for important tasks—like ensuring safety or accuracy in experiments. Want to know how it works? Let’s check out the formula next.
Formula for Specific Gravity to Density
The formula for finding density from specific gravity is simple:
ρ = SG × ρ_ref
Where:
- ρ = density of the substance (kg/m³ or g/cm³)
- SG = specific gravity (a number with no units)
- ρ_ref = density of the reference substance (usually 1000 kg/m³ or 1 g/cm³ for water)
Common Specific Gravity Values
Here are some examples:
- Hydrogen: 0.0000899
- Helium: 0.0001785
- Air: 0.001225
- Ethanol: 0.789
- Gasoline: 0.737
- Ice: 0.917
- Water: 1.000
- Aluminum: 2.700
- Iron: 7.870
- Copper: 8.960
- Silver: 10.490
- Lead: 11.340
- Gold: 19.320
- Osmium: 22.590
This formula comes from basic science rules. Water is the usual reference—its density is 1000 kg/m³ or 1 g/cm³—so you multiply the specific gravity by that to get the substance’s density. Pick your units (metric or others) and keep them consistent. Now, let’s make it easier with a table.
Quick Reference Table for Density from Specific Gravity
Why calculate every time? This table shows densities using water as the reference (1000 kg/m³), so you can look it up fast.
| Substance | Specific Gravity | Density (kg/m³) |
|---|---|---|
| Ethanol | 0.789 | 789 |
| Gasoline | 0.737 | 737 |
| Aluminum | 2.700 | 2,700 |
| Gold | 19.320 | 19,320 |
How to Use the Table
- Find your substance and its specific gravity.
- Check the density in the third column.
- Use it without doing math!
This table helps with searches like “density of gasoline from specific gravity.” For other substances, use the formula. Next, let’s try an example.
Example: Calculating Specific Gravity to Density
Suppose you have ethanol with a specific gravity of 0.789, and you want its density in kg/m³ using water’s reference density of 1000 kg/m³. Here’s how:
- Plug into the formula:
ρ = SG × ρ_ref
ρ = 0.789 × 1000 - Calculate:
0.789 × 1000 = 789
So, ethanol’s density is 789 kg/m³. This matches science data and helps you—like if you’re mixing ethanol or checking its weight.
Most Common FAQs
Converting specific gravity to density tells you how heavy a substance is in real units—like kg/m³. It’s useful for figuring out if something floats, how much it weighs, or how it fits in a space—like in engineering or chemistry projects.
You can find specific gravity values in science books, online databases, or product labels. For common stuff—like water or metals—charts list them, but for special materials, you might need to measure or look up the exact number.
No, but water is the most common reference because it’s simple—1 g/cm³ or 1000 kg/m³. If you use something else—like oil—you’d use its density instead, just make sure your units match up.