How to Calculate Linear Feet for LTL Freight (With Examples)

Linear feet is the length of trailer floor a load occupies. It is one of the simplest numbers in LTL planning, and one of the easiest to get wrong, because the answer depends on how the freight is packed — not just how long each unit is.

Ten 48-inch pallets laid end to end would be 40 feet. The same ten pallets, two across a 100-inch trailer, use 16.67 feet. Neither number is wrong arithmetic. Only one describes the trailer.

This guide shows the row-packing method, the orientation and stacking adjustments, and the pounds-per-linear-foot check that connects the floor plan to the carrier’s rating rules.

What linear feet means in freight

Linear feet (LF) is floor length measured from the nose of the trailer to the rear doors. It is a one-dimensional measure of a two-dimensional floor plan: the load may be 100 inches wide and 110 inches high, but the linear-foot number only counts how much of the trailer’s length is used.

That is why linear feet is not the sum of every unit’s length. If two pallets fit side by side across the trailer, they share the same row. The row uses one pallet depth of floor, not two.

Linear feet is also not cubic feet. Cube measures volume. A two-high stack can cut linear feet in half while leaving cube unchanged. A tall, light load can use little floor and a lot of cube. A short, heavy load can do the opposite.

The linear feet formula

There are four steps.

Step 1 — choose the side that runs down the trailer. That side is the row depth. The other side runs across the trailer.

Step 2 — count how many fit across.

units across = floor(usable trailer width ÷ side across)

Use the usable width, not the outside trailer width. A 53 ft dry van is commonly planned at about 100 inches of usable width, but lining, equipment, and the load itself can reduce it.

Step 3 — count the rows.

rows = ceil(floor positions ÷ units across)

Floor positions are the number of footprints that need floor space. Without stacking, that is the quantity. With stacking, divide the quantity by the number of tiers and round up.

Step 4 — add the row depths.

floor length (in) = rows × row depth + row gaps
linear feet = floor length ÷ 12

If the load has multiple line sizes, pack the rows rather than adding each line’s standalone length. The calculator does a deterministic first-fit packing: deeper units are placed first, and a row accepts another unit when its width still fits.

Worked example: ten GMA pallets

Take ten standard GMA pallets, 48 × 40 × 48 inches, at 500 pounds each. The trailer is a 53 ft dry van with 636 inches of usable floor length, 100 inches of usable width, and 110 inches of usable height.

40-inch side down

With the 40-inch side running down the trailer, the 48-inch side runs across.

100 ÷ 48 = 2 across
10 ÷ 2 = 5 rows
5 × 40 = 200 in
200 ÷ 12 = 16.67 linear feet

Two pallets share each row. Five rows use 200 inches, or 16.67 feet. That is 31.4% of the 636-inch floor.

48-inch side down

Rotate the pallets so the 48-inch side runs down the trailer.

100 ÷ 40 = 2 across
10 ÷ 2 = 5 rows
5 × 48 = 240 in
240 ÷ 12 = 20.00 linear feet

The count across does not change, but every row is 8 inches deeper. Five rows add 40 inches, or 3.33 feet. The same freight now uses 20 feet of floor.

This is the orientation trap. A calculator that assumes the longest side runs down the trailer would report 20 feet and miss the better plan.

Stacked two high

If the pallets can support a second tier and the trailer height allows it, five floor positions replace ten.

10 ÷ 2 tiers = 5 positions
100 ÷ 48 = 2 across
5 ÷ 2 = 3 rows
3 × 40 = 120 in
120 ÷ 12 = 10.00 linear feet

Stacking saves 6.67 feet, or 40% of the flat 40-inch-down result. The saving is not exactly half because the last row is only half full.

The load still weighs 5,000 pounds and still occupies 533.33 cubic feet. Density stays 9.38 lb/ft³ and the 2025 density class stays Class 100. Stacking changes floor use, not the freight’s density.

How orientation changes the answer

A rectangular handling unit has two possible rotations on the trailer floor. For each one, the side across the trailer determines how many fit, and the side down determines how deep each row is.

The best orientation is the one that produces the shortest total floor length after row packing. That is not always the rotation with the most units across. A rotation that fits one extra unit across but makes every row much deeper can still lose.

For the ten GMA pallets, both rotations fit two across, so the shorter row depth wins:

The calculator’s Auto setting compares both rotations for each line. You can also force a rotation when the load has a required door side, a forklift approach, or a label orientation.

Stacking: floor savings and limits

Stacking reduces the number of floor positions. It does not reduce the freight’s cube or weight. That distinction matters for rating and for trailer capacity.

Two limits control the stack:

• Trailer height. A 60-inch unit in a 110-inch trailer fits only one high, even if the product can support three. The calculator caps the tiers at the usable height and raises a notice.
• Product and packaging. The calculator can model a stack, but it cannot tell you whether the cartons, drums, or machinery can bear the load. That is a packaging and safety decision.

A stack can also create a partial last row. Ten pallets two high become five floor positions. At two across, that is three rows, not two and a half. The partial row still consumes a full row depth. Linear feet is a whole-row measure.

Mixed loads and row packing

Real shipments often have more than one pallet size. Adding each line’s standalone linear feet overstates the floor when different sizes can share a row.

The calculator packs the lines deterministically:

1. Each line gets an orientation and a row depth.
2. Each floor position becomes a placement with a width and a depth.
3. Placements are sorted deepest first.
4. Each placement goes into the first existing row where its width still fits; otherwise it starts a new row.
5. The row depth is the deepest placement in that row.

The combined result is the packed floor length. The per-line “shipped alone” number stays visible because a carrier may rate each handling unit separately, or a warehouse may load the lines in a different sequence.

A simple example: three 48 × 40 pallets and two 60 × 48 skids. The skids are deeper, so they are placed first. The pallets fill the remaining width where they fit, then start new rows. The result is a specific floor plan, not an average.

Linear feet vs cube vs density class

These three numbers answer different questions:

Density and class use total gross weight and total cube. They do not use linear feet. The 2025 NMFC density scale maps lb/ft³ to one of 13 classes, from Class 400 below 1 lb/ft³ to Class 50 at 50 lb/ft³ or more. Classes 77.5, 110, 150, 200, and 500 remain commodity-specific and are not density outputs.

A load can be dense enough for a low class and still be awkward on the floor. A light, bulky load can use a lot of linear feet without weighing much. That is why the calculator reports both, and why neither number replaces the carrier’s tariff.

For the class side of the calculation, see how to calculate freight class and the 2025 freight class chart.

The pounds-per-linear-foot check

Pounds per linear foot (lb/LF) is total gross weight divided by linear feet:

lb/LF = total gross weight ÷ linear feet

For the ten GMA pallets at 16.67 feet, 5,000 ÷ 16.67 = 300 lb/LF. Stacked at 10 feet, the same load is 500 lb/LF. The freight did not get heavier. The same weight now sits on less floor.

Why check it? Some LTL tariffs use a linear-foot rate basis, a minimum weight per linear foot, or a cubic-capacity threshold. The trigger, the measurement method, the minimum charge, and the exceptions vary by carrier, contract, and service. There is no single national threshold you can apply to every quote.

The practical approach is:

1. Calculate linear feet and lb/LF for the load.
2. Ask the carrier or broker which linear-foot or capacity rule applies to the quote.
3. Compare the load with that specific rule.
4. Confirm any minimum charge or accessorial before booking.

The calculator deliberately does not apply a carrier-specific threshold. It gives you the two numbers the conversation needs.

Typical trailer dimensions

These are planning values, not manufacturer specifications. Usable width and height vary with the trailer, lining, and equipment, and the calculator lets you edit every dimension.

A 53 ft van at 100 inches wide fits two 48-inch pallets across with 4 inches to spare. It does not fit three 40-inch pallets across, because 3 × 40 = 120 inches. Width is often the constraint that decides the row count.

A quick checklist

Before you use a linear-foot number:

• Measure the handling unit as tendered, including the pallet, overhang, top caps, and wrap.
• Use the usable trailer width, not the outside width.
• Compare both orientations; do not assume the longest side goes down the trailer.
• Check that the product can actually bear a stack, and that the trailer height allows it.
• Pack mixed sizes into rows instead of adding standalone lengths.
• Add any required row gaps, blocking, or inaccessible floor space.
• Calculate lb/LF and compare it with the carrier rule that applies to the quote.
• Confirm the final load plan with the carrier and the loading crew.

The bottom line

Linear feet is a packing result, not a sum. Choose the orientation, count across, round up to whole rows, and add the row depths. Then check the stack and the pounds per linear foot.

The Linear Feet Calculator does the row packing and shows the orientation comparison, the trailer fit check, and the 2025 density class as secondary context. For the rating side, use the Freight Class & Density Calculator.