How much does a gallon of isopropyl alcohol weigh?
A US gallon of 99% (anhydrous) isopropyl alcohol weighs about 6.55 pounds (2.97 kg) at 20 °C. That figure comes from IPA’s density of 0.785 g/mL, verified on PubChem. Because isopropyl alcohol is lighter than water (8.34 lb/gal), a drum of IPA weighs noticeably less than the same volume of water. Diluted grades such as 70% and 91% weigh more, because the added water is heavier than the alcohol.
What is the weight of isopropyl alcohol per gallon and liter?
Isopropyl alcohol (IPA, isopropanol, 2-propanol) has a density of 0.785 g/mL at 20 °C. Multiplying that density by the volume of a container gives its net weight. Use the values below to convert any volume of 99% IPA to weight.
| Measure of 99% IPA | Weight (at 20 °C) |
|---|---|
| Density | 0.785 g/mL (0.785 kg/L) |
| 1 liter | 0.785 kg (1.73 lb) |
| 1 US gallon | 6.55 lb (2.97 kg) |
| 1 imperial (UK) gallon | 7.87 lb (3.57 kg) |
| 5-gallon pail (net) | ~32.8 lb (14.9 kg) |
| 55-gallon drum (net) | ~360 lb (163 kg) |
| Water, for comparison | 8.34 lb/gal (1.00 kg/L) |
To convert quickly: gallons × 6.55 = pounds of 99% IPA. For a precise figure at your storage temperature, request the density listed on the batch Certificate of Analysis (CoA), since density falls slightly as temperature rises.
Why do 70% and 91% isopropyl alcohol weigh more per gallon?
Lower-concentration grades are IPA blended with water. Water is denser than isopropyl alcohol (1.00 g/mL versus 0.785 g/mL), so the more water a grade contains, the more a gallon weighs. A gallon of 70% IPA is heavier than a gallon of 99% IPA for that reason. Water and IPA form a non-ideal mixture, so the exact density of each blended grade is best taken from its CoA rather than estimated. As a rule of thumb, per-gallon weight rises as concentration drops.
How do you calculate the weight of an IPA drum or tote?
Net product weight equals volume multiplied by density; gross weight adds the empty container (tare) weight.
- 55-gallon drum: 55 gal × 6.55 lb/gal ≈ 360 lb of 99% IPA, plus roughly 40–50 lb for a steel drum.
- 275-gallon IBC tote: 275 gal × 6.55 lb/gal ≈ 1,801 lb of product, plus tote tare.
- 330-gallon IBC tote: 330 gal × 6.55 lb/gal ≈ 2,162 lb of product, plus tote tare.
Need a fast conversion for a different volume or grade? Use the RightPath conversion tools to move between gallons, liters, pounds, and kilograms.
How does isopropyl alcohol compare in weight to other solvents?
Most common lab and industrial alcohols and solvents are lighter than water, and their per-gallon weights cluster closely together. The table compares net weight per US gallon at 20 °C, using densities from PubChem.
| Liquid | Density (g/mL, 20 °C) | Weight per US gallon |
|---|---|---|
| Isopropyl alcohol (99%) | 0.785 | 6.55 lb |
| Ethanol | 0.789 | 6.58 lb |
| Acetone | 0.791 | 6.60 lb |
| Methanol | 0.791 | 6.60 lb |
| Water | 1.000 | 8.34 lb |
Isopropyl alcohol is the lightest of these common alcohols per gallon, though the differences among IPA, ethanol, acetone, and methanol are small—roughly 0.05 lb per gallon.
Does temperature affect the weight of isopropyl alcohol?
Yes. Like most liquids, isopropyl alcohol expands as it warms, so its density—and therefore its weight per gallon—decreases slightly as temperature rises. The 0.785 g/mL figure is measured at 20 °C, the standard reference temperature. For custody transfer, tank gauging, or precise batch weights, use the density stated on the CoA at the reference temperature rather than an ambient reading. For most ordering and freight estimates, the 6.55 lb/gal value is close enough.
What grades and sizes of isopropyl alcohol does RightPath stock?
RightPath Industries supplies isopropyl alcohol (IPA) 99% along with 91%, 70%, 70% with USP-grade WFI, 60% with USP water, and 40% grades. See the full alcohols category for related products. Typical packaging includes 5-gallon pails, 55-gallon drums, 275- and 330-gallon IBC totes, and bulk tank truck or rail quantities. Grade selection depends on your application—electronics cleaning, disinfection, extraction, or as a process solvent—and the required purity or water specification.
How do you order bulk isopropyl alcohol from RightPath?
Request a quote through our bulk pricing form with your grade, volume, and packaging. RightPath confirms current density and specifications on the CoA, arranges drum, tote, or bulk delivery, and can set up recurring or just-in-time shipments. For physical-property references, the authoritative source is the PubChem record for isopropyl alcohol (CID 3776).
Frequently asked questions
What is the density of isopropyl alcohol?
Isopropyl alcohol has a density of 0.785 g/mL (0.785 kg/L) at 20 °C, per PubChem. This equals about 6.55 pounds per US gallon.
How much does a 55-gallon drum of isopropyl alcohol weigh?
A 55-gallon drum holds about 360 lb (163 kg) of 99% IPA as net product weight. Add roughly 40–50 lb for a steel drum to get gross shipping weight.
Is isopropyl alcohol lighter than water?
Yes. Isopropyl alcohol’s density is 0.785 g/mL versus water at 1.00 g/mL, so IPA is about 21% lighter. A gallon of IPA weighs 6.55 lb compared with 8.34 lb for water.
Does 70% isopropyl alcohol weigh more than 99%?
Yes. 70% IPA contains more water, and water is denser than isopropyl alcohol, so a gallon of 70% IPA weighs more than a gallon of 99% IPA.
How do you convert gallons of IPA to pounds?
Multiply the number of US gallons by 6.55 to get the weight in pounds of 99% isopropyl alcohol. For example, 20 gallons × 6.55 = 131 lb.