Cattle trailer capacity calculator: head per compartment by weight
Enter the cattle's average weight and the inside floor size of each compartment. The calculator gives the recommended maximum head for each, from a 2025 extension loading chart, with horn and heat adjustments.
Built and checked by Mike Shelton · Updated · Free, no sign-up
Maximum head
16
recommended maximum
Cattle weight
12,800 lb
10.3 sq ft per head
- Compartment 1 (168 sq ft)
- 16 head · chart
Loading chart Mississippi State University Extension P2797, Transporting Beef Cattle by Road (Aug 2025), Table 1Checked October 2026 · Maximums for typical feeder cattle; mature or fat cattle need more room. Check gross and axle weights too.
About 16 head at 800 lb for this trailer. Want loads planned around sale days and the 28-hour law? Our dispatchers book freight your rig is built for at 5% of gross, and you approve every load.
Get loads for my rigHow the calculator works
- Exact chart match: when a compartment is one of the chart's floor sizes (14 to 34 ft long, 6 or 7 ft wide) and the weight is one of its weights, the chart's head count is used.
- Any other floor: head = floor area ÷ square feet per head, rounded down.
- Square feet per head comes from the chart's largest floor, 34 by 7 ft, divided by its head count at each weight, with straight-line steps between weights.
- Horns: 5% fewer head, rounded down.
Square feet per head by weight
| Weight (lb) | 400 | 600 | 800 | 1,000 | 1,200 | 1,400 |
|---|---|---|---|---|---|---|
| Sq ft per head | 5.2 | 7.7 | 10.3 | 13.2 | 15.9 | 17.0 |
These areas are derived from Table 1 of Mississippi State University Extension Publication P2797, "Transporting Beef Cattle by Road" (August 2025). Mississippi State University Extension P2797, Transporting Beef Cattle by Road (Aug 2025), Table 1Checked October 2026 The chart gives maximums for typical feeder cattle; the publication notes fewer mature or fat cattle fit the same trailer.
Worked example
EXAMPLEA pot has four compartments measured at 12 by 7.5 ft, 15 by 7.5 ft, 15 by 7.5 ft and 10 by 7.5 ft, and the cattle average 850 lb. At about 11.1 sq ft per head, the compartments take 8, 10, 10 and 6 head: 34 in all, about 28,900 lb of cattle. If the cattle are horned, each compartment drops by 5%, rounded down, and the total falls to 30. On a 95 °F afternoon, load fewer than that.
Measuring your trailer
Measure inside, on the floor the cattle stand on. On a stock trailer, run the tape from the front wall to the rear gate and across from side to side; ignore the gooseneck unless it is floored and gated for cattle. On a pot, measure each compartment on its own, since decks, nose and belly differ in length and sometimes width. Enter half-feet where you have them. A few inches across a long trailer can change the count by a head.
Using the result at the sale barn or ranch
Agree on the head count and average weight when the load is booked, then check the cattle when they come up the alley. If they are heavier than promised, horned, or the afternoon is hot, recalculate and load fewer. Write the final count on the paperwork. The shipper knows the cattle, but the hauler drives them, so the hauler makes the final call on how many go in each compartment.
Common mistakes
- Entering the trailer's outside length instead of the inside floor.
- Guessing the average weight instead of asking for the sale or scale weight.
- Loading every compartment to the maximum on a hot day.
- Mixing bulls, cows and calves in one compartment.
- Rounding up a compartment that comes out at 9.8 head; the chart's numbers are maximums, so round down.
- Forgetting to recheck the count when cattle are added or swapped at a second pickup.
What the result means
The number is a recommended maximum, not a target. Cattle need enough room to stand and keep their footing, but not so much that they are thrown around when the truck brakes. Load heavier cattle toward the front and keep different groups in separate compartments. Then check the truck: the cattle weight plus the rig's empty weight should stay within the 80,000 lb Interstate gross 23 CFR 658.17(b)Checked October 2026 and your axle limits.
Time matters as much as space: animals generally can't be confined more than 28 consecutive hours without unloading for feed, water and rest. 49 U.S.C. 80502(a)Checked October 2026 Plan the run with the 28-hour law timer, read the full loading chart in how many cattle fit on a trailer and the cattle hauling guide, and see livestock dispatch or the GearLoads home page.
Cattle trailer capacity calculator FAQ
01How does the cattle trailer capacity calculator work?
It uses Mississippi State Extension's 2025 loading chart. If your floor size and weight match a row in the chart exactly, it uses the chart's head count. Otherwise it divides the floor area by the square feet per head for your cattle's weight, interpolated between the chart's weights, and rounds down. Horned cattle are cut by 5%.
02How do I measure a pot trailer compartment?
Measure the inside floor the cattle stand on, wall to wall and gate to gate, for each compartment on each deck: the nose, the upper and lower decks and the belly. Enter each one separately. Don't use the trailer's outside length, and don't count floor behind closed gates or areas cattle can't reach.
03Should I load fewer cattle in hot weather?
Yes. The extension guidance says to reduce the number of head when it is hot and to avoid the hottest part of the day, typically 11 a.m. to 4 p.m. The calculator's numbers are maximums for normal conditions; in heat, load below them and keep the trailer moving with good airflow.
04Does the calculator check the truck's weight?
It shows the total weight of the cattle, but not the truck's gross or axle weights. Add the cattle weight to your truck and trailer's empty weight and check it against the 80,000 lb Interstate limit and your axle groups. Finished cattle in a full pot can approach the limit.