Fiber drum sizes and dimensions guide
A straight answer on diameters, heights, and capacities, from someone who sells them every day.
Published August 24, 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 don't always 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 6 to 77 gallons across Mauser’s standard North American product line, although other manufacturers offer different ranges.
- Common diameters: 14" to 23", usually in 1.5" steps between sizes
- Example common size: One 30-gallon Lok-Rim model measures 18.5" in inside diameter and 26" in inside height.
- 1G specification maximum: Federal construction standards permit a maximum capacity of 450 liters and a maximum net mass of 400 kg. An individual drum may be rated for substantially less.
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.
How much bigger is a large drum, really?
Widths are proportional to actual diameter, heights are illustrative only. Source: Mauser Packaging Solutions fiber drum brochure; The Cary Company spec sheet (#26W31F).
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
Mauser’s North American lock-ring fiber drum line uses diameters from 14" to 23", generally in 1.5" increments, and covers nominal capacities from 6 to 77 gallons. Other manufacturers use different size ranges and increments.
Square Ro-Con drums use length-and-width measurements rather than a conventional round-drum diameter. Available dimensions and weight ratings vary by model, so buyers should use the applicable Greif specification sheet rather than compare them directly with round-drum diameters. 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.
The 30-gallon Lok-Rim model shown in the cited specification measures 18-1/2" in inside diameter by 26" in inside height and 19-3/8" in outside diameter by 27" in outside height. 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.
These are maximum limits within the federal 1G fiber-drum specification, not the approved capacity or weight rating of every fiber drum. 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.
Where common sizes sit against the legal maximum
Illustrative, not to scale. Marked sizes are commonly sold capacities referenced earlier on this page. Source: 49 CFR § 178.508.
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 North American round-drum line uses a defined set of diameters, while square Ro-Con drums use different length-and-width dimensions. Two drums with the same nominal gallon capacity can therefore have different outside footprints and heights. That means two drums both labeled "30 gallon" from different manufacturers can differ slightly in exact diameter and height.
What is the maximum size allowed by the federal 1G fiber-drum specification?
The 1G construction standard sets maximum limits of 450 liters in capacity and 400 kg in net mass. The amount that may actually be shipped in a particular drum depends on that drum’s UN marking, tested design, condition, contents and the applicable hazardous-material packaging requirements.
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. North American diameter options from 14" to 23" and a capacity range of 6 to 77 gallons (11 to 291 liters), 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 21,000 total orders through 2026. Archived and dead-deal orders are excluded.
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