Freight class calculator.

Freight class is a single number that tells a less-than-truckload carrier how costly your freight is to move compared with everything else on its trailers. The scale runs from class 50, the least expensive, to class 400, the most expensive. A low class means dense, compact freight that stacks well and is hard to damage. A high class means light, bulky or awkward freight that fills a trailer long before it gets heavy. The classes come from the National Motor Freight Classification, the NMFC, which the National Motor Freight Traffic Association (NMFTA) maintains. Each carrier then applies its own rates to each class, so two shipments of the same weight can price very differently. The calculator above estimates class from density, which is now the primary basis for most commodities (opens in a new tab). The rest of this page explains the math, the exceptions, and how to keep the class on your bill of lading from changing after pickup.

Freight class applies to less-than-truckload shipping, where your pallets share a trailer with freight from other shippers. The LTL carrier picks up, runs your freight through one or more terminals, and delivers it alongside other customers' orders. Because many shipments compete for the same trailer, the carrier needs a common way to compare a pallet of steel fasteners with a pallet of foam cushions. Class does that job. Full truckload works differently: you buy the whole trailer for the lane, so the carrier does not care how dense your freight is, only whether it fits and stays legal on weight. The NMFTA guidance and the v12 note on this tool say the same thing in plain terms: truckload and partial pricing don't use class at all. If you ship four pallets, class matters. If you ship 26, you are buying a truck, and the question becomes floor space and payload, which our pallet planner answers.

The NMFC is published by the NMFTA, a nonprofit made up of motor carriers, and it assigns classes to thousands of commodities through numbered items. Carriers that participate in the NMFC reference it in their tariffs, and the class on your bill of lading points the carrier to the right line in that tariff. The NMFTA describes the NMFC as a voluntary standard (opens in a new tab): no federal agency writes the classes, and a carrier's own tariff and contract terms decide how it applies them. That matters in two ways. First, your LTL contract can override the published class with a negotiated one, sometimes called a freight all kinds or FAK rating. Second, disputes about class are settled under the carrier's tariff and the NMFC rules, not by a regulator. Changes to the NMFC go through a docket process, where proposals are published, argued and voted on before they take effect.

On July 19, 2025, NMFTA Docket 2025-1 (opens in a new tab) moved many commodities from fixed, item-specific classes to density-based classification. Before the change, a commodity description such as "furniture, upholstered" carried its own class or a short density table written just for that item. After the change, a large share of items point to a general density scale instead. The same docket expanded that density scale from 11 sub-provisions to 13, which added finer breaks at the dense end where much industrial freight sits. The practical effect for shippers is simple: you need accurate dimensions and weights for every LTL shipment, because the class now comes straight from them. A shipper who copied the same class onto every bill of lading for years may now be wrong on some lanes and products. If you have not rerun your products since the change, do it now, one handling unit at a time, using the calculator above.

The current NMFC density scale has 13 tiers (opens in a new tab), and the calculator uses exactly these breaks. Each lower bound is inclusive and each upper bound is exclusive, so freight at exactly 12.0 lb per cubic foot is class 85, not 92.5.

Read the table from the top: the lighter the freight for its size, the higher the class. Notice how wide the bands get at the dense end. Freight anywhere from 15 to just under 22.5 lb per cubic foot lands in class 70, so a small measuring error there rarely moves the class. At the light end the bands are narrow, and an inch of height can cost you a full class. At the dense end, three classes (60, 55 and 50) cover everything from 30 lb per cubic foot up, so heavy freight near 35 or 50 still needs accurate numbers.

Density is weight divided by volume, measured as you hand the freight to the carrier. The calculator does these steps for you, but knowing them lets you check any quote or rebill by hand.

1. Measure length, width and height in inches at the widest points, including the pallet.
2. Multiply the three to get cubic inches.
3. Divide by 1,728, the number of cubic inches in a cubic foot (12 x 12 x 12), to get cubic feet.
4. Weigh the piece in pounds, again including the pallet and wrap.
5. Divide the weight by the cubic feet. The result is pounds per cubic foot.
6. Find that density in the 13-tier table to get the class.

The calculator works per piece: it computes density from one piece's dimensions and weight, then multiplies cubic feet and weight by the number of pieces for the totals. Identical pieces share the same density, so the class does not change with the count. If your pieces differ, run each one separately, as covered further down this page.

The calculator opens with a common case, a 48 x 40 in pallet stacked to 48 in tall and weighing 650 lb. The 48 x 40 in footprint (opens in a new tab) is the most common pallet size in the United States, so this is a useful benchmark. Here is the math, step by step.

At 12.19 lb per cubic foot, this pallet sits just above the 12.0 break. If it weighed 640 lb instead, the density would be 640 / 53.33 = 12.00, still class 85 because the lower bound is inclusive. At 630 lb the density drops to 11.81 and the class rises to 92.5. Ten pounds of product, or a heavier pallet you forgot to weigh, can move the class. That is why the scale weight on your bill of lading should come from a scale, not from a product sheet.

Light, bulky freight is where class gets expensive, so run these numbers before you quote a price to your own customer. Take a pallet of boxed foam cushions: 48 x 40 in footprint, stacked to 72 in tall, 300 lb including the pallet.

At 3.75 lb per cubic foot the cushions land in class 250, near the top of the scale. Now see what packaging can do. Compress the same product so the stack stands 60 in tall: 48 x 40 x 60 = 115,200 cu in, divided by 1,728 is 66.67 cu ft, and 300 / 66.67 = 4.50 lb per cubic foot. That is class 175, a full tier lower, for the same product and the same weight. For light goods, retail displays and furniture, cube reduction is often the cheapest freight saving available, and it costs nothing at the carrier's end.

Dense freight sits at the bottom of the scale, and the 2025 expansion added finer breaks there. Take a pallet of bagged mortar mix: 48 x 40 in footprint, 36 in tall, 2,000 lb including the pallet.

The density lands exactly on the 50.0 break. Because the lower bound of each band is inclusive, the class is 50, the lowest on the scale. If the same pallet were stacked 1 in taller, at 37 in, the volume becomes 71,040 cu in, or 41.11 cu ft, and the density falls to 2,000 / 41.11 = 48.65. That is class 55. Heavy freight near a break is worth measuring twice. For loads like this, which you also see in building materials, weight often limits a trailer long before space does, which changes the conversation once you move past LTL.

When a shipment has pieces of different sizes or weights, run each piece through the calculator on its own. The tool computes density for one piece at a time and multiplies by the piece count, so mixing a tall light pallet with a short heavy one in one entry would give a wrong answer. Suppose you ship the 650 lb standard pallet from the first example with the 300 lb cushion pallet from the second. Separately they are class 85 and class 250. Combined, they total 950 lb across 53.33 + 80.00 = 133.33 cu ft, a density of 950 / 133.33 = 7.13 lb per cubic foot, or class 125. Whether a carrier rates the pieces separately or the shipment as a whole depends on how the lines are written on the bill of lading and on the carrier's tariff. Ask before you tender. List different commodities on separate lines with their own weights, piece counts and NMFC items, because blending them can raise the class of the dense item.

The fastest way to lower a class is to change the numbers that go into density, and three levers matter most. First, height. On the default 48 x 40 in pallet at 650 lb, a 60 in stack is 115,200 cu in, or 66.67 cu ft, for a density of 9.75 and class 100. The same goods at 48 in are class 85. Second, footprint. Freight that overhangs a pallet by an inch on each side is measured at the overhang, which adds volume without adding product. Third, pallet choice. A heavier pallet raises weight without changing volume, which lowers class slightly, but it also raises the billable weight, so it rarely saves money. The calculator lets you test each lever in seconds: change one dimension, watch the density and class update. Run the test before you design new packaging or agree a price with a customer, because the class you quote is the class you will be held to.

Density decides most classes now, but it does not decide all of them. The NMFTA guidance says classification still considers four transportation characteristics (opens in a new tab): density, handling, stowability and liability. Density takes priority when the other three raise no special concern. When they do, a commodity can carry a class that differs from what the density scale alone would give.

A freight-all-kinds agreement or a carrier-specific rule can also override the published class. The calculator only knows density, which is why its result is labelled an estimate. In practice, the shipper's job is to describe the freight honestly: name the commodity precisely, flag anything fragile or unstackable, and mark hazardous materials as the rules require. A carrier that discovers a handling or stowability problem at the dock can apply a different class and accessorial charges.

Some commodities carry their own NMFC item and class regardless of density, and the calculator cannot know which ones. That is the plain warning on the tool itself, and it is the most common reason a density estimate and a carrier invoice disagree. The item number on your bill of lading is what ties your freight to the right class, so look it up rather than guessing. The NMFTA publishes the classification, and your LTL carrier can confirm the item for a commodity you ship regularly. When you have the item, check whether it points to a fixed class or to the density scale. If it points to the density scale, the calculator result should match. If it carries a fixed class, use that class and note it, because a density-based class on the bill of lading will be corrected at the carrier's terminal. Keep a short internal list of your products with their item numbers, dimensions and weights, and review it whenever the NMFC changes.

Measure the shipment exactly as the carrier will see it: built, wrapped and on its pallet. The rule is to measure the shipment as tendered, including the pallet and any overhang (opens in a new tab). A few habits prevent most disputes.

• Measure length and width at the widest point, which is often the overhang of a carton, not the pallet edge.
• Measure height from the floor to the highest point, including the pallet and any top cap or corner boards.
• Use whole inches and do not round down, because the carrier's dimensioner will not.
• Measure after the load is wrapped, since stretch wrap and bulging cartons add volume.
• Measure every pallet on a mixed shipment, not just the first one.

Irregular freight, such as a machine on a skid, is measured as the smallest rectangular box that would contain it. That box, not the machine's own shape, sets the cubic feet. Write the dimensions on the bill of lading, because a recorded measurement is your best evidence if the class is later challenged.

The weight that sets density is the weight of the whole handling unit, so weigh it after it is built. That includes the pallet, slip sheets, stretch wrap, banding and any dunnage. A product sheet that lists unit weights times quantity misses all of those, and on a light load they can be enough to cross a break, as the 650 lb example showed when 20 lb moved the pallet from class 85 to class 92.5. A floor scale or a pallet jack with a built-in scale gives you a number you can defend. Record the weight per handling unit, not just the shipment total, so a rebill can be checked piece by piece. If you ship the same product repeatedly, weigh a few finished pallets and use the heaviest as your standard figure. Underweighing to reach a lower class does not work for long: carriers weigh freight at their terminals, and a corrected weight comes with a corrected class.

A reclassification happens when the carrier decides your freight belongs in a different class from the one on the bill of lading, and it rebills you at the new rate. LTL terminals measure freight with dimensioning equipment, weigh it on certified scales and sometimes open or photograph shipments to confirm the commodity. When their numbers disagree with yours, the carrier issues a correction, often with an inspection certificate listing the measured dimensions and weight. Reclassifications usually trace back to one of four causes: an unmeasured pallet, an estimated weight, a wrong commodity description or an NMFC item with a fixed class. Each one is preventable. If you receive a correction you think is wrong, ask for the inspection record and any photos, then compare them against your own recorded dimensions, weights and item number. A dispute is far easier to win when the bill of lading shows real measurements, rather than a class copied from an old shipment.

A short routine before each LTL pickup prevents almost every class dispute. It takes a few minutes per shipment and pays for itself the first time a rebill does not arrive.

1. Build and wrap each handling unit as it will ship.
2. Measure every unit at its widest points, including the pallet and overhang.
3. Weigh every unit on a scale, including the pallet and packaging.
4. Run each unit through the calculator and note density and class.
5. Look up the NMFC item for each commodity and check for a fixed class.
6. Write dimensions, weights, piece counts and item numbers on the bill of lading, one line per commodity.
7. Photograph each unit with a tape measure in frame before pickup.
8. Keep the photos and the bill of lading together until the invoice clears.

If the calculator puts a unit within a few tenths of a break, consider changing the build. A slightly shorter stack or a lighter pallet on the right side of the line is often worth more than any rate negotiation.

Class only applies while your freight is small enough to ship LTL, and the larger a shipment gets, the less it matters. Once you fill a meaningful share of a trailer, two other services usually price better. A partial truckload puts your freight on a truck with one or two other shipments, often without terminal handling, and is priced on the floor space and weight you use rather than on class. A full truckload buys the whole trailer for the lane, and the carrier prices the truck, not the commodity. For light, high-class freight, the switch point comes sooner than many shippers expect, because a class 250 pallet pays LTL rates built for low density while taking the same floor space as any other pallet. Run your pallet count through the pallet planner to see how many feet of trailer you would use. When that number starts to approach a large share of a 53 ft trailer, ask for a partial or truckload rate alongside the LTL quote.

The calculator gives you an estimated class to check an LTL quote, and it also gives you the numbers a truckload broker needs. When you request a quote from us for a partial or full truckload, the useful inputs are the ones you just measured: pallet count, footprint, height, weight per pallet, total weight and whether the freight can stack. Our rates come from a person, not a formula, and those numbers are what that person works from. For manufacturing shippers with mixed SKUs, a clean list of handling units also speeds up trailer planning and appointment booking. For retail and consumer goods, where light cartons often push LTL into high classes, the same list shows quickly whether a partial would cost less than several LTL shipments. Keep the calculator result as a record, but quote the truck on its own terms: space, weight, equipment and the lane. The freight glossary explains the related terms if a carrier's invoice uses a word you have not seen.