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Store a frequently used density in this browser. Saved entries never leave your device.
Recent calculations
Formula used
Gallons measure volume, while pounds measure weight. Density connects these two measurements. The selected gallon standard determines the liters used.
Gallons to pounds: lb = gallons × fill fraction × liters per gallon × density in kg/L × 2.20462262185
Pounds to gallons: gallons = pounds ÷ 2.20462262185 ÷ density in kg/L ÷ liters per gallon
Temperature adjustment uses adjusted density = base density × correction factor ÷ [1 + α(T − Tref)]. This remains an engineering estimate. Verify critical loads using measured product data.
How to use this calculator
- Select the conversion, batch, or comparison mode.
- Choose the correct US, Imperial, or dry gallon.
- Select a substance or enter a custom density.
- Set temperature, fill percentage, containers, and tare weight.
- Choose precision, then press the calculate button.
- Review formulas, export results, or save a custom substance.
Example gallon-to-pound values
| Substance | Volume | Approximate density | Approximate weight |
|---|---|---|---|
| Fresh water | 1 US liquid gallon | 0.9982 kg/L | 8.33 lb |
| Milk | 1 US liquid gallon | 1.030 kg/L | 8.60 lb |
| Gasoline | 1 US liquid gallon | 0.745 kg/L | 6.22 lb |
| Diesel fuel | 1 US liquid gallon | 0.832 kg/L | 6.95 lb |
Frequently asked questions
Can gallons convert directly to pounds?
No. You must know the material density and gallon standard.
How many pounds are in one gallon of water?
One US liquid gallon of water weighs about 8.33 pounds near 20°C.
Why do gasoline and water have different weights?
Gasoline has a lower density than water, so equal volumes weigh less.
What is the difference between US and Imperial gallons?
An Imperial gallon contains more liters than a US liquid gallon.
What is a US dry gallon?
It is a volume unit mainly associated with dry commodities.
Does temperature change the answer?
Yes. Many liquids expand when heated, reducing density and weight per gallon.
What does fill percentage mean?
It applies only the occupied portion of each nominal container volume.
What is tare weight?
Tare weight is the empty container weight added to material weight.
What does the safety margin calculate?
It increases gross load for planning, handling, or structural allowance.
Can I enter density in pounds per gallon?
Yes. The calculator interprets it using your selected gallon standard.
Are preset material densities exact?
No. They are approximate values and should not replace supplier specifications.