Storage planning tool

Storage unit size calculator

Build a structured inventory, set a conservative usable stack height and access aisle share, then compare the estimate with nominal floor sizes before checking a real facility.

Plan nominal storage area

Estimate occupied floor area from measured inventory, a conservative stack height, and an access aisle share.

Measurement unit

Set a conservative usable height; this does not assess stacking safety.

Share of total floor area reserved for access. Tested range: 0-50%.

Inventory

Item 1
Item 2

Required planning area

23.25 sq ft

Occupied estimate: 18.60 sq ft

5 × 10 nominal unitSchematic only, not a placement plan
Nominal unit boundary
Aisle allowance
Occupied estimate

Calculated required area is within this nominal boundary; this is not a fit guarantee.

18.60 sq ft
Occupied estimate
23.25 sq ft
With aisle share
50 sq ft
Nominal boundary

Storage area estimate calculated

Required planning area: 23.25 sq ft. Smallest listed candidate: 5 × 10 nominal unit.

Required planning area: 23.25 sq ft

Volume-and-footprint screening only, not a packing or facility decision.

Input recap

Rows
2
Usable stack height
5.00 ft
Access aisle share
20%
Entry units
Imperial

Assumptions

  • Volume divided by usable stack height is a planning abstraction, not a packing algorithm or a placement plan.
  • Items use full rectangular envelopes; no compression, nesting, shape, weight, stackability, or packing efficiency is inferred.
  • Usable stack height is a user-set conservative input, not a stacking-safety statement.
  • Unit labels and floor dimensions are nominal provider sizes; actual interior dimensions and availability vary by facility.
  • Item assumptions and storage-unit sizes use dataset version 2026-07-10.2.

Inventory composition

Each row uses its complete rectangular envelope.

Calculated load composition by inventory row
ItemEnvelopeQtyVolumeBasis
U-Haul medium moving box18.125 × 18 × 16 in1030.21 cu ftofficial product dimensionsCalculated as a rectangular envelope from current U-Haul product dimensions.
Three-seat sofa envelope84 × 38 × 34 in162.81 cu fteditorial assumptionEditorial rectangular planning envelope; measure the actual sofa. It is not a manufacturer or industry standard.

Calculation

93.01 cu ft ÷ 5.00 ft = 18.60 sq ft; 18.60 sq ft ÷ (1 - 20%) = 23.25 sq ft

Occupied floor area = total item volume ÷ usable stack height. Required area = occupied area ÷ (1 - aisle share).

Candidate comparison

Nominal unitAreaArea comparisonFootprint screen
5 × 5 nominal unit25 sq ft1.75 sq ft remaining1 item footprint warning
5 × 10 nominal unit50 sq ft26.75 sq ft remainingNo footprint conflict found
5 × 15 nominal unit75 sq ft51.75 sq ft remainingNo footprint conflict found
10 × 10 nominal unit100 sq ft76.75 sq ft remainingNo footprint conflict found
10 × 15 nominal unit150 sq ft126.75 sq ft remainingNo footprint conflict found
10 × 20 nominal unit200 sq ft176.75 sq ft remainingNo footprint conflict found
10 × 25 nominal unit250 sq ft226.75 sq ft remainingNo footprint conflict found
10 × 30 nominal unit300 sq ft276.75 sq ft remainingNo footprint conflict found

Smallest listed candidate satisfying both checks: 5 × 10 nominal unit. Verify the actual unit before renting.

Oversized footprint review: Item 2 exceeds one or more smaller nominal units.

Limits to verify

Verify the actual unit interior, door opening, columns, ceiling, fire rules, stacking and weight rules, access aisle, and availability with the facility.

This planner does not infer door clearance, loading path, access, stacking safety, climate features, security, or facility availability.

Oversized-item checks compare only each rectangular L × W footprint with nominal floor dimensions in two planar orientations.

Check the actual unit interior, door opening, columns, ceiling, fire rules, stacking and weight rules, access aisle, and availability with the facility. This is not a packing algorithm.

Sources and dataset

Nominal floor labels come from the current U-Haul size guide. Each facility offers a different size mix; availability and actual interior dimensions vary.

Predefined furniture rows are editorial envelopes. Measure every actual item.

Source check: July 10, 2026.

Dataset version: 2026-07-10.2

Nominal size reference

Storage unit size chart

Compare the eight nominal floor sizes used by this calculator. The provider groups these labels as small, medium, or large, but the label alone does not describe the usable interior.

Nominal sizeFloor areaProvider size group
5 × 5 ft25 sq ftSmall
5 × 10 ft50 sq ftSmall
5 × 15 ft75 sq ftMedium
10 × 10 ft100 sq ftMedium
10 × 15 ft150 sq ftMedium
10 × 20 ft200 sq ftLarge
10 × 25 ft250 sq ftLarge
10 × 30 ft300 sq ftLarge

Before renting, verify the actual interior dimensions, door opening, columns, facility rules, and availability. Nominal labels and offered sizes vary by location.

Provider grouping checked 2026-07-10. See Sources and dataset for the recorded guide and dataset details.

Guides for this calculation

Check the measurements, assumptions, and worked examples in the related guides. Return to Storage planning for the full decision sequence, or review the tool methodology for formulas and limits.