Moving Truck Size Calculator

Background.

Rental counters sell moving trucks by length — 10 feet, 15, 20, 26 — but the question on moving day is whether the sofa, the beds, the bikes and eighty-odd boxes go in one load. Get it wrong one way and you are driving back across town for a second trip with the clock running on the rental; get it wrong the other way and you have paid for, fuelled and parked a truck far bigger than the job.

The catch is that belongings never pack a truck the way water fills a tank. A dining table stands on legs with empty space beneath, a mattress has to go on edge against a wall, a glass-fronted cabinet cannot carry a stack of boxes, and you need room to tie the load down and reach the last items. So a household whose items add up to 900 cubic feet needs noticeably more than 900 cubic feet of cargo box. The loading-efficiency figure captures that gap: it is the share of the truck's interior you expect to fill with actual belongings.

The calculation runs in a fixed order. It divides your belongings volume by the loading efficiency, adds a percentage buffer for whatever the inventory missed, then adds a flat allowance for any awkward item that needs extra clearance. The result is set against the capacity of the truck you are considering, which gives the number of trips, the space left over and, if it doesn't fit, how much is left behind. Optional rental and mileage figures turn the plan into a rough cost.

Volume is the only thing being checked. A truck can reach its weight limit long before it looks full if the load is books, tools and tile, and nominal sizes vary from one rental company and model to the next, so the capacity worth entering is the usable cargo volume of the specific truck.

What is moving truck size calculator?

Moving truck size, in the sense used here, is the cargo volume in cubic feet that a household or office move needs, compared with the usable cargo volume of a particular truck, trailer or container. Belongings volume is the space the items themselves occupy. Loading efficiency is the fraction of a truck's interior that a real load can fill once gaps, protective padding, stacking limits and access are allowed for. The buffer is a percentage margin for uncertainty in the inventory. Trips required is the number of full loads the candidate truck needs, rounded up to a whole trip. Unused capacity and overflow are both measured against a single load: what is left empty when everything fits, or what is left behind when it doesn't.

How to use this calculator.

1. 01Enter your estimated belongings volume in cubic feet. Measure the big pieces — length × width × height in inches, divided by 1,728 — and add the boxes by their dimensions, or carry over a total from a moving-box estimate. Remember the garage, shed and balcony.
2. 02Set the loading efficiency. The default of 80% suits a typical household mix; go lower for a furniture-heavy or fragile load that cannot be stacked, and higher only for a load that is mostly uniform boxes.
3. 03Add a buffer percentage for what the inventory may have missed. A careful room-by-room list can carry a small buffer; a rough guess deserves a larger one.
4. 04Use the bulky-item adjustment for a piano, a large sectional or gym equipment that needs clearance around it. It is added in cubic feet after the buffer, not scaled by efficiency.
5. 05Enter the candidate truck's usable cargo capacity from the rental company's specification, or measure the cargo box. The trips figure is what the volume needs; enter the number of trips your schedule and the rental window allow and the trip check says whether the load fits within them.
6. 06If you want a cost, enter the daily rate, the mileage charge and the planned miles, including the miles for any extra trip.

The formula.

Required volume V = I ÷ e × (1 + b) + B, and trips = ⌈V ÷ C⌉. I is the belongings volume in cubic feet, e the loading efficiency as a decimal (80% is 0.80), b the buffer as a decimal (5% is 0.05), B the bulky-item allowance in cubic feet and C the candidate truck's capacity. The ceiling brackets mean round up: a load needing 1.02 truckloads takes two trips. Unused capacity is C − V when that is positive and zero otherwise; overflow is V − C when that is positive and zero otherwise, so exactly one of them is zero.

The order matters. Efficiency is applied first because it converts item volume into truck volume, and the buffer then scales that truck volume, so a 5% buffer on 1,125 cubic feet adds 56.25. The bulky-item allowance comes last and is not scaled at all: 60 cubic feet entered there adds exactly 60. If you would rather a big item were treated like everything else, include its volume in the belongings figure instead.

Efficiency sits in the denominator, which makes it the most sensitive setting. Dropping it from 80% to 70% raises the efficiency-adjusted volume by a seventh, about 14.3%, while the buffer works in straight proportion. The optional cost is the daily rate plus the mileage rate times the planned miles; it is not multiplied by days or trips, and fuel, insurance, taxes and deposits are not included. None of this checks weight, which has to be judged against the truck's payload rating separately.

A worked example.

Frequently asked questions.

References& sources.

1. [1]Federal Motor Carrier Safety Administration (2024). "Consumer Rights and Responsibilities." U.S. Department of Transportation.
2. [2]Federal Motor Carrier Safety Administration (2023). "Rights and Responsibilities Booklet." U.S. Department of Transportation.
3. [3]National Institute for Occupational Safety and Health (2021). "Applications Manual for the Revised NIOSH Lifting Equation." CDC/NIOSH Publication No. 94-110.
4. [4]ASTM International (2025). "ASTM D5118/D5118M-22: Standard Practice for Fabrication of Fiberboard Shipping Boxes." ASTM.
5. [5]National Institute of Standards and Technology (2026). "NIST Handbook 133, Appendix E: General Tables of Units of Measurement." U.S. Department of Commerce.