Moving / Calculator
Storage unit size calculator
Calculated unit size
104.6 sq ft calculated floor area
Size screen only; verify dimensions and safe packing with the facility.
View calculation breakdownCalculation breakdown
| Component | Amount |
|---|---|
| Item volume, cu ft | 340 |
| Usable stacking height, ft | 5 |
| Packing utilization | 65% |
| Required floor area, sq ft | 104.6 |
| Selected floor area, sq ft | 150 |
Methodology
Item volume = box count × box volume + furniture volume. Required floor area = item volume ÷ (usable stacking height × utilization fraction). Select the smallest listed unit meeting both area and the entered rectangular item footprint, allowing 90° rotation.
Draft engineering scope: volume and footprint screen only. No 3D packing, door-clearance, ceiling, weight, access, stack-safety, vehicle-fit, or facility-availability guarantee. At zero volume, no unit is selected. Oversize inputs return a custom-size result.
The calculator first estimates item volume as box count x volume per box + furniture or other item volume. It then divides that volume by usable stacking height x the utilization fraction to estimate required floor area. The utilization setting accounts for the portion of the theoretical stacked space you expect to use after gaps and access space. The calculator also checks the entered rectangular footprint of the largest item, allowing a 90-degree rotation. It selects the smallest listed unit that satisfies both the required floor area and that footprint check. With the default inputs, 30 boxes x 3 cu ft plus 250 cu ft of furniture equals 340 cu ft. Dividing by 5 ft of usable stacking height and 65% utilization gives about 104.62 sq ft of required floor area; the expected selection is a 10 ft x 15 ft unit with 150 sq ft of floor area. This is a volume-and-footprint screen rather than a three-dimensional packing plan. Door clearance, exact item dimensions, access, weight, safe stacking, vehicle fit, and facility availability still need to be checked directly. At zero item volume no unit is selected, and inputs beyond the listed choices return a custom-size result.
Example assumptions
| Input | Example |
|---|---|
| Number of boxes | 30 |
| Volume per box (cu ft) | 3 |
| Furniture / other item volume (cu ft) | 250 |
| Usable stacking height (ft) | 5 |
| Space used after gaps / access (%) | 65 |
| Largest item: longer footprint side (ft) | 7 |
| Largest item: shorter footprint side (ft) | 3 |
Nominal unit footprints: 5 × 5 ft (25 sq ft); 5 × 10 ft (50 sq ft); 5 × 15 ft (75 sq ft); 10 × 10 ft (100 sq ft); 10 × 15 ft (150 sq ft); 10 × 20 ft (200 sq ft); 10 × 25 ft (250 sq ft); 10 × 30 ft (300 sq ft).
Frequently asked questions
How is required floor area calculated?
The calculator totals the estimated cubic volume of boxes and other items, then divides that volume by usable stacking height and the utilization fraction. Lower stacking height or lower utilization requires more floor area.
What does packing utilization mean?
It is the share of the theoretical stacked volume you expect to use after allowing for gaps and access. For example, 65% utilization means the calculator assumes 65% of the height-adjusted space is effectively used.
Why does the calculator ask for the largest item's footprint?
A unit can have enough total floor area but still be too narrow for one large item. The calculator checks the entered longer and shorter footprint sides against the listed unit dimensions and also allows a 90-degree rotation.
How does the default example lead to a 10 x 15 unit?
The default items total 340 cu ft. At 5 ft of usable stacking height and 65% utilization, they require about 104.62 sq ft of floor area. The expected listed unit meeting the area and footprint checks is 10 x 15 ft, or 150 sq ft.
Does a suggested unit guarantee everything will fit?
No. The calculation does not perform three-dimensional packing or verify doors, ceilings, access paths, weight limits, safe stacking, vehicle fit, or facility availability. Confirm those details with the storage facility before choosing a unit.