Figuring out 500-gallon propane tank dimensions is fairly easy. That’s because all 500-gallon propane tanks have standardized dimensions (length, width, total footprint, and even weight). This is true for all big overground or underground horizontal residential propane tanks (100-gallon, 125-gallon, 250-gallon, 325-gallon, 500-gallon, 750-gallon, 1000-gallon, and 2000-gallon propane tanks).
Namely, all the standardized specs of a 500-gallon propane tank are put forward by The American Society Of Mechanical Engineers (ASME for short).
In their chart, you will find everything from 500-gallon propane tank diameter, length, total empty weight, shell thickness, head thickness, and height with different AG, AD, or UG domes (height-wise, the 500-gallon propane tank can be up to 62-inches tall due to inclusion of different domes on top of this torpedo tank).
Here is a visual depiction of some of the 500-gallon propane tank dimensions (we cover all of them in the standardized specs list further on):

The only problem ASME propane tank specifications table is not widely available. That’s why we will list all the 500-gallon propane torpedo tank dimensions here to see how big is a 250-gallon propane tank:
500 Gallon Propane Tank Specifications (Standardized Specs List)
Here is the full list of 500-gallon propane tank specs, including size and weight:
- Diameter: 37 inches. All 500-gallon propane tanks have a diameter of 37 inches (or 3 feet and 1 inch). That means that the standard 500-gallon propane tank is 37 inches wide and 37 inches high (total height with AG, AD/UG, 18-inch UG, and 24-inch UG domes can be up to 62-inches – check the end of the specs list).
- Length: 119 inches. All 500-gallon propane tanks are 119 inches long (or 9 feet and 11 inches).
- Total Empty Weight: 949 lbs. 500-gallon propane tanks are quite heavy. They weigh 949 lbs when empty. When you fill them with 400 gallons of propane (further on, we explain why you can only put 400 gallons of propane in a 500-gallon propane tank; it’s the 80% rule for safety reasons), a full 500-gallon propane tank weighs 2593 lbs. This comes from 4.11 lbs/gallon propane density at 77°F temperature.
- Shell Thickness: 0.218 inches. This means that the wall thickness of the 500-gallon propane tank is 0.218 inches.
- Head Thickness: 0.185 inches.
- Leg Width: 4 inches. That means that the legs the 500-gallon propane tank is standing on are 4 inches wide; this is relevant for above-ground propane tanks.
- Leg Distance From Shell Edge: 4 inches. This means that the legs are 4 inches away from the end of the propane tank.
- Leg Distance From Center Of Leg: 11 inches.
- Shell Width: 60 Inches.
- Height With AG Dome: 46 inches.
- Height With AD/UG Dome: 47 inches.
- Height With 18-Inch UG Dome: 56 inches.
- Height With 24-Inch UG Dome: 62 inches.
These are all standardized 500-gallon propane tank specifications. Most homeowners will be interested in how long and how heavy is a 500-gallon propane tank. The addition of other specs here will help out even the experienced propane tank installers.
119 inches (length of 500 gal. Tank) is 9’11”, not 11’11”
Hi Gordon, thanks for the heads-ups. We fixed the typo; now the numbers are in order.