Fiber drum sizes and dimensions guide
A straight answer on diameters, heights, and capacities, from someone who sells them every day.
Published August 4, 2026
By John Anderson, Owner of Verde Trader
10+ years buying and selling used industrial packaging.
Fiber drum sizes get confusing fast, because "30 gallon" isn't a fixed set of dimensions. Every manufacturer runs its own diameter and height increments, and inside dimensions never match outside dimensions. I've pulled the actual spec sheets and the regulation that sets the legal ceiling so you can see real numbers instead of rounded marketing figures.
Fiber drum sizes at a glance
- US capacity range: roughly 5 to 75 gallons (about 20 to 284 liters) across standard product lines
- Common diameters: 14" to 23", usually in 1.5" steps between sizes
- Most common size: 30 gallon, about 18.5" diameter x 26" tall on the inside
- Legal maximum: 450 liters (119 gallons) and 400 kg (882 lb) net mass for a 1G fiber drum under DOT rules
Fiber drum size ranges by region
Open-top fiber drums are generally produced in a 10 to 270 liter capacity range (about 2 to 60 imperial gallons), across a wide mix of diameters, heights, and cross sections. In practice, most drums sold in the US and Europe cluster into two separate sizing systems that don't line up cleanly with each other.
Fiber drums come in a wide range of heights and diameters even within a single capacity class.
In the US, drums are sized in gallons and inches. In Europe, they're sized in liters and millimeters, and the European construction standard (BS EN 12710) covers a 15 to 250 liter range. If you're sourcing internationally, don't assume a "30 gallon" drum and a "115 liter" drum are the same footprint, they usually aren't.
Standard US fiber drum diameters and capacities
Lock ring fiber drums, the most common style sold in North America, run from about 14" to 23" in diameter, typically moving in 1.5" increments between sizes. That range covers capacities from roughly 4.5 to 75 gallons (11 to 284 liters).
Square-cornered drums like Greif's Ro-Con line use a different diameter set entirely, from 9-9/16" up to 21.5", with weight-rated constructions at 60, 115, 150, 225, 300, and 400 lb. Greif's round Lok-Rim line spans a wider 6.5 to 75 gallon range in the same family.
Source: Mauser Packaging Solutions fiber drum brochure; Greif Ro-Con and Lok-Rim fibre drum spec sheets.
Real fiber drum spec sheet examples
Here's what the numbers actually look like on manufacturer spec sheets, since "inside" and "outside" dimensions are rarely the same drum.
A 30 gallon Lok-Rim fiber drum measures 18-1/2" diameter x 26" tall on the inside, but 19-3/8" diameter x 27" tall on the outside once you account for the sidewall and chime. The same size drum is rated for 225 lb with a plastic lever-lock cover, or 300 lb with a plain metal cover, at a tare weight of roughly 10 to 10.5 lb.
Source: The Cary Company product spec sheets (Part #26W31F, #26WF3U); BioSpectra 50kg fiber drum specification sheet, v1.1, December 2025.
The regulatory size maximum for fiber drums
Fiber drums are classified under DOT hazmat regulations with the identification code 1G. Under 49 CFR 178.508, that code caps the drum at 450 liters (119 gallons) of capacity and 400 kg (882 lb) of net mass.
This is a legal ceiling, not a typical commercial size. Almost every fiber drum actually sold, used or new, falls well under 75 gallons. If you see a drum advertised near the 119 gallon mark, check the spec sheet closely.
Choosing the right fiber drum size for your product
Diameter and height both affect how much weight a drum can safely hold and how it stacks.
A bigger diameter doesn't automatically mean more usable capacity. Weight-rated construction (the 60 to 400 lb ratings you'll see on spec sheets) is often the real limit for dense products, well before the drum fills up by volume. For light, bulky material, volume runs out first.
If you're comparing used inventory, always check inside dimensions against your product's fill height, and outside dimensions against your pallet footprint and truck cube. See our fiber drum pricing guide for how size affects what a drum costs, and browse our current fiber drum inventory to see real sizes in stock.
Frequently asked questions about fiber drum sizes
What's the difference between a fiber drum's inside and outside dimensions?
The outside dimensions include the sidewall thickness, the chime, and the closure ring, so they run larger than what's actually usable inside. On a 30 gallon drum, that's the difference between 18-1/2" inside diameter and 19-3/8" outside diameter. Always check which measurement a listing is using before you assume a drum will fit your rack or fixture.
Do all manufacturers use the same size increments?
No. Mauser's US lock ring line steps diameters in 1.5" increments, while Greif's Ro-Con line uses a different, less regular set of diameters. That means two drums both labeled "30 gallon" from different manufacturers can differ slightly in exact diameter and height.
What's the largest fiber drum I can legally ship for hazardous materials?
Under DOT rules, a 1G fiber drum tops out at 450 liters (119 gallons) and 400 kg (882 lb) net mass. That's a regulatory ceiling, not a common size. Most hazmat-rated fiber drums actually sold are 55 gallons or smaller.
Does a square Ro-Con drum save real storage space compared to a round drum of the same capacity?
Yes, in two ways. Empty Ro-Con drums of the same size nest together, so you can fit twice as many in a truckload as conventional round drums. Filled drums also palletize tighter, since square footprints don't leave the gaps between drums that round ones do.
Sources
This page combines the federal regulation that sets fiber drum size limits, a peer-reviewed packaging technology reference, and current manufacturer spec sheets, alongside our own sold-order records.
Industry standards (what is defined)
- 49 CFR § 178.508, Standards for fiber drums. Sets the 1G identification code and the legal maximum capacity (450 L / 119 gal) and net mass (400 kg / 882 lb) for a fiber drum.
Manufacturer specifications
- Mauser Packaging Solutions, fiber drum brochure. US diameter range (14" to 23", 1.5" steps) and capacity range (4.5 to 75 gal / 11 to 284 L), plus the separate European diameter and liter range.
- Greif, Ro-Con fibre drum spec sheet. Diameters and weight-rated constructions for Greif's square, space-saving fiber drum line.
- Greif, Lok-Rim fibre drum spec sheet. Overall capacity range for Greif's round lock ring drum line.
- The Cary Company, 30 Gallon Fiber Drum, Plastic Cover w/Lever Lock Ring (Part #26W31F). Inside and outside diameter/height, capacity, and tare weight for a real 30 gallon drum.
- The Cary Company, 30 Gallon Fiber Drum, Plain Metal Cover w/Lever Lock (Part #26WF3U). Same size drum with a metal cover and 300 lb NMFC net weight limit.
Background and reference
- Kirwan, M.J. (ed.), Handbook of Paper and Paperboard Packaging Technology, 2nd ed., Chapter 7: Fibre drums. Global capacity range (10 to 270 L), typical pack weights, and the European BS EN 12710 construction standard range (15 to 250 L).
Our sales data (what people actually pay)
- Verde Trader sold-order data. More than [ORDER COUNT] fiber drum orders through [DATE]. Archived and dead-deal orders are excluded.
