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RescueLoad

    Trailer cube and load volume calculator: will it cube out or weigh out first?

    Enter your equipment's inside length, width, height and legal payload, then the shipment's piece size, weight and count. The calculator shows the cubic feet used, the share of payload used, and which runs out first.

    Equipment

    Inside sizes and payloads vary by maker and spec. Replace these starting values with yours.

    in
    in
    in
    lb

    Shipment, per piece

    in
    in
    in
    lb

    Load volume

    800 ft³ of 1,664 ft³

    Cube used48%
    Weight used (5,400 of 10,000 lb)54%

    This freight weighs out first: at most about 22 pieces by weight.

    Geometry only. Gaps between pieces, freight that can't stack and axle weights all lower the real number.

    Pallet cube
    Example
    Cube
    800.0 ft³
    Weight
    5,400 lb
    Density
    6.75 lb/ft³
    Class estimate
    125

    Estimate only: the carrier's tariff and your NMFC item decide. Band from the density scale in NMFC Docket 2025-1, checked 2026-10-10.

    800 ft³ and 5,400 lb uses 48% of the space and 54% of the payload. Our dispatchers check both before an offer reaches you, and you approve every load.

    Get loads that fit my equipment

    This trailer cube and load volume calculator answers two questions at once: how much space the shipment takes, and whether your equipment runs out of space or weight first. Enter the inside measurements of your 26 ft box, van or reefer, its legal payload, and the size, weight and count of the pieces. The results update as you type.

    How it is calculated

    1. Equipment cube. Inside length × inside width × inside height, in inches, ÷ 1,728 = cubic feet.
    2. Shipment cube. Piece length × width × height ÷ 1,728, times the number of pieces.
    3. Shares. Shipment cube ÷ equipment cube = cube used. Shipment weight ÷ legal payload = weight used.
    4. Verdict. The calculator works out how many pieces of that size fit by space alone and how many by weight alone. The smaller number is the limit: if space runs out first the load cubes out; if weight does, it weighs out.

    The presets are typical starting values, not a standard. Inside sizes vary by body builder and trailer maker, and payload depends on your truck's empty weight and ratings.

    26 foot box truck cubic feet, worked out

    26 ft box with 12 palletsExample

    1. BOX312 × 96 × 96 in inside = 2,875,392 in³ ÷ 1,728 = 1,664 ft³
    2. PIECE48 × 40 × 60 in = 66.7 ft³, 450 lb
    3. LOAD12 pieces = 800 ft³ and 5,400 lb
    4. SHARES48% of the cube, 54% of a 10,000 lb payload
    5. LIMITAbout 24 pieces by space, 22 by weight: this freight weighs out first

    Those are the calculator's defaults. The payload in particular is an EXAMPLE: yours comes from your own scale ticket and ratings.

    How to read the result

    The two bars matter more than the big number. If the cube bar is well ahead of the weight bar, you're hauling air: rates for light freight should reflect the space it takes, not its weight. If the weight bar leads, the trailer will look half empty at the legal limit, which is normal for dense freight. If either bar goes red, the shipment doesn't fit as entered.

    Cube isn't the whole story. Pieces need floor positions, and some can't stack, so plan the floor in the trailer load planner, and work out what you can carry with the max payload calculator. For the sizes behind the presets, see our guide to freight truck sizes; for how much freight moves by truck at all, the US freight shipping statistics (coming soon).

    Reefers lose cube

    A reefer's insulated walls, floor channels and the air space the unit needs make its inside smaller than a dry van of the same length. Air has to move around the load, so packing a reefer to the roof or the walls can damage the freight. Use the reefer's real inside sizes and leave the airflow space the shipper or the unit maker calls for.

    Pricing cube-out freight

    Rates per mile hide the difference between light and dense freight. A cube-out load fills your box at a fraction of your payload, so nothing else can ride with it; it should pay for the whole space. A dense load at the weight limit can leave floor open for nothing, because you can't add weight. Partial loads sit in between: knowing the cube and weight of each lets you see whether two partials going the same way fit together before you agree to either rate.

    Mistakes that skew the answer

    • Using outside dimensions. Measure inside, wall to wall and floor to ceiling.
    • Forgetting the door. A roll-up door can lower the usable height near the rear.
    • Leaving out the pallet. It belongs in each piece's height and weight.
    • Using the gross rating as payload. Subtract the empty weight first.

    Light freight and dense freight pay differently, and the right mix keeps your truck full without going over. Our reefer dispatch team, like every desk here, checks cube and weight before an offer reaches you. Send an application.

    Questions about this calculator

    How many cubic feet is a 26 ft box truck?
    Multiply the inside length, width and height in inches and divide by 1,728. A box measuring 312 inches long, 96 wide and 96 high inside has about 1,664 cubic feet. Bodies differ in inside height, wall thickness and how much of the length sits over the cab, so measure yours with a tape and enter the numbers in the calculator.
    Is the 26 foot box truck cubic feet the same as its usable space?
    No. The cube is the empty box. Usable space is smaller once you allow for gaps between pallets, freight that can't be stacked, the wheel wells and anything mounted on the walls. A load that the calculator says fills 90 percent of the cube may not fit in practice, so leave a margin and check the floor layout.
    What does cube out mean in trucking?
    A load cubes out when it fills the trailer's space before it reaches the legal payload. Light, bulky freight like furniture, foam or empty containers cubes out. The opposite is weighing out: dense freight like steel, paper or drinks reaches the weight limit with floor and height to spare. Knowing which helps you price the load and plan what else can ride.
    How do I use a cubic feet calculator for freight?
    Measure each piece at its longest, widest and tallest points, including the pallet. Multiply length by width by height in inches, divide by 1,728 for cubic feet, and multiply by the number of pieces. Add the weight of every piece. Compare both totals with your equipment's inside cube and legal payload, which is what this calculator does.
    How do I find my legal payload?
    Payload is what you may carry: the gross weight rating or legal limit, whichever is lower, minus the truck's empty weight with fuel and driver. Weigh your empty rig on a certified scale and subtract that from the rating on the door sticker or your registered weight. The max payload calculator walks through it.