Freight Class Calculator

density in pounds per cubic foot = gross weight ÷ volume, where volume = (length × width × height in inches) ÷ 1,728, and the class is the band that density falls in

handling unit

The freight as it is tendered — one pallet, one crate, one drum, measured at its longest, widest and highest points with the packaging and any overhang included. Density is worked out per handling unit rather than once for a whole shipment, which is also how carriers do it: the published guidance for density-based classification says to measure the pallets and the packaging around the actual goods, and to repeat the measurement for each pallet.

gross weight

The goods plus their packaging, not the net weight of the contents. It is the figure the bill of lading carries, and the one a carrier's own weigh-in will be compared against when the shipment is re-classed.

volume

Length × width × height of the handling unit in inches, divided by 1,728 for cubic feet. Measure to the outermost point of the packaged freight rather than to the product inside it — the wooden corner a crate is built around is part of the volume it occupies.

density

Pounds per cubic foot. Light and bulky lands low on the scale and is charged more; dense freight lands high and is charged less. That is the opposite of the intuition that heavy freight costs more, and it follows from what fills a trailer first.

freight class

A number from the NMFC's own ladder — 50, 55, 60, 65, 70, 77.5, 85, 92.5, 100, 110, 125, 150, 175, 200, 250, 300, 400, 500. Lower is cheaper to ship. The class a density band gives you is the density provision's answer only, and it applies to commodities whose item carries a density provision.

Use it when you are quoting or booking LTL freight and want to see what the carrier is looking at, or when a class on an invoice looks wrong and you want to work back to the density it implies. Do the density first and the class second: density is the part you can compute from your own paperwork before anyone else touches the shipment, and it is the part that most often turns out to be wrong, because the dimensions on a product spec sheet are the product's rather than the packaged freight's. It is also the quick way to see why two shipments of the same goods quote differently — a pallet that grew three inches taller when the packaging changed can cross a band edge and come out a class higher, and once you can see the edge you can see whether it is worth rebuilding the pallet. What it does not tell you is what you will pay. A density-based freight class is one input to a rate, and the rate also depends on distance, weight, the accessorials that apply and the carrier's own tariff.

1. A 48 × 40 × 36 in pallet at 500 lb

   1. Volume: 48 × 40 × 36 = 69,120 in³, and 69,120 ÷ 1,728 = 40 ft³
   2. Density: 500 ÷ 40 = 12.5 lb/ft³
   3. 12.5 lb/ft³ falls in the band that runs from 12 up to but not including 15, which is class 85
   4. In metric: 12.5 × 16.0185 = 200.2 kg/m³

   This is the worked example the freight guides tend to reach for, and it is a good one to check your own numbers against: 48 × 40 in is the standard North American pallet footprint, 36 in is a common build height, and 500 lb is a load two people can move with a pallet jack. The class is 85 and the density sits in the middle of its band, so nothing about this shipment is sensitive to a measurement being an inch out.

2. The same footprint, taller and far lighter

   1. Volume: 48 × 40 × 60 = 115,200 in³, and 115,200 ÷ 1,728 = 66.67 ft³
   2. Density: 60 ÷ 66.67 = 0.9 lb/ft³
   3. 0.9 lb/ft³ is below 1, so it takes the bottom band — class 400
   4. In metric: 0.9 × 16.0185 = 14.4 kg/m³

   Read this against the first example. Same footprint, same carrier, same lane: 500 lb is class 85 and 60 lb is class 400. The light pallet is the expensive one, which is the part of freight classification people find hardest to accept, and it is not a quirk — a trailer runs out of space long before it runs out of weight, so light freight costs the carrier more per pound to move. It also means the lever is usually the packaging. Cutting six inches off this height takes 6.7 ft³ off the volume and lifts the density from 0.9 to 1.0 lb/ft³, which is the lower edge of the next band up, so the shipment drops from class 400 to class 300 — and 1.0 is a band edge, so an inch either side of it matters.

3. 14 lb/ft³, the edge the published charts disagree on

   1. Volume: 48 × 40 × 36 = 69,120 in³, and 69,120 ÷ 1,728 = 40 ft³
   2. Density: 560 ÷ 40 = 14.0 lb/ft³ exactly
   3. 14.0 lb/ft³ falls in the band that runs from 12 up to but not including 15, so the class is 85 — the upper edge of a band belongs to the band above it, and 15.0 would be class 70
   4. In metric: 14.0 × 16.0185 = 224.3 kg/m³

   Hold on to this one if you have been reading carrier help pages. The density chart that several carriers publish puts 14 lb/ft³ at class 77.5, where the density scale in force since 19 July 2025 puts it at 85. The two disagree in the other direction as well: at 8.5 lb/ft³ the chart says 110 and this scale says 100. That is not a rounding difference — 85 and 77.5 are different rate bases — and it is not something this page can settle for you. Ask your carrier which of the two they rate on before you build a pallet around either answer.

Everything here is arithmetic, and the arithmetic is exact — the uncertainty is entirely in what goes into it and in what the answer is allowed to decide. Density does not set a freight class by itself. The NMFC writes density provisions into individual commodity items, so a shipment is only rated on density if the item its commodity falls under has one; commodities classed on their description, or on a specific published class, are not moved by anything on this page. Where density does apply, it is one of four factors the Freight Classification Development Council weighs — density, handling, stowability and liability — and packaging that is awkward to stow or easy to damage can pull a class up even when the density is good. The thirteen bands shown here took effect on 19 July 2025 and replaced a scale that gave lower classes at the same density; a tariff or a chart printed before that date will disagree, and an older chart is the most common reason a shipment comes back at a class this page does not predict. Read the bands as half-open — each includes its lower bound and excludes its upper — because that is how the provisions are written, and it means 14.999 and 15.0 lb/ft³ are two different classes. Rounding a measurement up to the next whole pound per cubic foot can therefore cost a class, which is why the same pallet measured twice by two people can come back two ways. The measurement itself is to the outermost point of the packaged freight, with overhang and pallet included, and the weight is gross rather than net; measuring the product instead of the freight is the single most common way a density comes out too high and a class too low. Nothing here averages a mixed shipment, and nothing here is a price. A class is one input to a rate alongside distance, weight, accessorials and the carrier's tariff, and carriers re-weigh and re-measure, so a class quoted from these numbers can change once the shipment is in their hands. Nor is LTL the only regime a shipment can fall under: parcel carriers rate light packages on dimensional weight rather than on a freight class, and full truckload is priced on the lane rather than on density at all.

How do I work out a freight class from density?

Measure the handling unit to its outermost points and multiply the three dimensions in inches, then divide by 1,728 to get cubic feet. Divide the gross weight in pounds by that volume to get pounds per cubic foot. Take the class from the band that density falls in on the density scale that has been in force since 19 July 2025 — under 1 lb/ft³ is class 400, 12 to just under 15 is 85, and 50 or more is class 50. A 48 × 40 × 36 in pallet at 500 lb is 40 ft³, which is 12.5 lb/ft³ and class 85.

Is density the only thing that sets a freight class?

No, and this is the part that trips people up. Density provisions live inside individual NMFC commodity items, so a shipment is rated on density only if the item its commodity falls under has one. Where density does apply it is one of four factors — density, handling, stowability and liability — and the Freight Classification Development Council weighs all four when it writes or reviews an item. Freight that is fragile, that cannot be stacked, or that needs special handling is classed up for those reasons even when its density-based freight class would be lower, and a commodity with its own published class is rated on that instead.

Why does a freight class chart give me a different number?

Because the chart a carrier publishes is not the same ladder as the density provisions. The chart circulating on carrier help pages lists eighteen classes and cuts its bands at different densities: at 14 lb/ft³ it says class 77.5 where the density scale says 85, and at 8.5 lb/ft³ it says 110 where the scale says 100. The disagreement runs in both directions, so you cannot correct for it by adding or subtracting a class. This page computes the density scale, because that is what the classification writes into an item; a chart is a carrier's own recommendation for estimating. Before you build a pallet around either answer, ask the carrier that will rate the shipment which one they use.

What counts as one handling unit?

The freight as it is tendered — one pallet, one crate, one drum — measured at its longest, widest and highest points with the packaging and any overhang included. Density is per handling unit, not per shipment: if a trailer holds a dense pallet and a light one, the density of each is what matters, and dividing total weight by total volume produces a number that describes neither and can land both in the wrong band. The published guidance for density-based rating says the same thing in the same order — measure the shipment including the pallets and other packaging, and repeat the step for each pallet on a multiple-pallet shipment.

Why is light freight a higher class than heavy freight?

Because a trailer fills up on space long before it reaches its weight limit, so a light shipment occupies capacity the carrier could have sold to a dense one. The density scale prices that: under 1 lb/ft³ is class 400 and 50 lb/ft³ or more is class 50, so the same footprint carrying 60 lb instead of 500 lb goes from class 85 to class 400. The practical consequence is that when a light shipment quotes badly, the fix is usually in the packaging — knocking six inches off a 60 in build takes a 66.67 ft³ pallet down to 60 ft³ and its density from 0.9 to 1.0 lb/ft³, which crosses a band edge and drops it from class 400 to class 300.

What happens at the edge of a density band?

Each band includes its own lower bound and excludes its upper one, the way the provisions are written: a density of exactly 15.0 lb/ft³ is class 70, not class 85, and exactly 1.0 lb/ft³ is class 300, not class 400. The top band is open-ended — 50 lb/ft³ or more is class 50 with no ceiling, so there is no such thing as freight too dense to classify. The edges matter because they are where measurement decides the answer: a density of 14.999 and one of 15.0 are two different classes, and one shipping department rounding a measurement up while another rounds it down is enough to explain a class that changes between quotes.

• Freight Classification Docket 2025-2 — the density subprovisions in §I Subject 13 (Sub 1 to Sub 13, from "Less than 1" at class 400 to "50 or greater" at class 50), effective 19 July 2025 — National Motor Freight Traffic Association
• Classification 101: Mastering the Precise Process of Classifying Freight — the four factors (density, handling, stowability, liability) and what each one covers — National Motor Freight Traffic Association
• NMFC — the classification itself, its class ladder from 50 to 500, and how commodity items carry provisions — National Motor Freight Traffic Association
• Freight Class Help Content — a carrier's eighteen-class density chart (class 77.5 at 13.5–15 lb/ft³ and class 110 at 8–9 lb/ft³, the two bands that disagree with the density scale), and the measuring rule that packaging is included and each pallet measured separately — Amazon Freight