Storage Unit Size Calculator
Add up your furniture and boxes to find the right self-storage unit size — 5x5 through 10x30 — with buffer room for aisles and stacking.
Living room (sofa, tables, TV)
≈ 80 sq ft each
Bedroom set (bed, dresser, nightstands)
≈ 60 sq ft each
Kitchen boxes & small appliances
≈ 20 sq ft each
Medium moving boxes
≈ 1.5 sq ft each
Large appliance (fridge, washer)
≈ 15 sq ft each
Outdoor/patio furniture
≈ 30 sq ft each
Renting by square footage without knowing your actual square footage
Storage facilities sell units in a handful of standard sizes — 5×5, 5×10, 10×10, 10×15, 10×20, 10×30 — and the sizing guidance most people get is a vague verbal description (“10×10 fits a one-bedroom apartment”) that may or may not match their actual belongings. This calculator works from the other direction: add up the actual footprint of what you’re storing, item by item, and it recommends the smallest standard unit that comfortably fits it, with a realistic buffer built in — a more reliable approach than matching your situation to someone else’s rough description of “about a one-bedroom’s worth of stuff.”
Why the buffer matters more than people expect
A storage unit’s floor space and your items’ combined footprint aren’t the same usable quantity, and treating them as equal is the most common way people end up renting a unit that’s technically big enough on paper but frustrating to actually use. You need aisle space to reach items without unloading half the unit every time you need something near the back, and stacking — while it does add real capacity — rarely achieves the clean, gap-free efficiency a flat square-footage sum implicitly assumes. This calculator’s 20% buffer above your raw item footprint is a planning margin specifically meant to keep the unit usable, not just technically sufficient.
Building an accurate item list
The most useful way to fill in this calculator is category by category — group furniture by room (living room set, bedroom set) rather than trying to individually itemize every small object, and use the box count for everything smaller that gets packed rather than trying to estimate its footprint directly. Large appliances and outdoor furniture deserve their own line items since they take up disproportionate floor space relative to how “big” they feel to think about. If you’re genuinely unsure about an item’s footprint, err toward overestimating slightly — the buffer already built into the recommendation gives some slack, but a badly underestimated item list can still land you a size short.
Drive-up versus climate-controlled: a real cost-versus-protection tradeoff
Once you know the size you need, the next decision is unit type. Drive-up units let you back a vehicle right up to the door for loading and are typically the cheaper option, but they’re exposed to more temperature and humidity swings since they’re not fully climate-controlled. Indoor, climate-controlled units cost more but meaningfully protect anything sensitive to temperature extremes or humidity — wood furniture that can warp or crack, electronics, photographs, important documents, and anything with adhesives or finishes that degrade in heat. For a short-term storage need with sturdy, weather-tolerant items, a drive-up unit is often the more economical choice; for longer-term storage or anything genuinely valuable or sensitive, the added cost of climate control is frequently worth it.
Vehicles and oversized items need their own conversation
Storing a car, boat or RV is a different sizing question than household items — a car alone typically needs at least a 10×20 unit, and many facilities offer dedicated outdoor or covered vehicle storage separate from standard indoor units, often with different insurance or running-condition requirements. If a vehicle is part of what you’re storing, confirm sizing and any facility-specific requirements directly with the storage facility rather than relying solely on this calculator’s household-item-focused estimate. See the moving cost calculator if storage is part of a larger move, and the land area calculator for converting between area units if a facility quotes dimensions differently than you’re used to.
How this is calculated
Total footprint = sum of (item footprint × quantity) for everything included Recommended unit = smallest standard size ≥ total footprint × 1.2 buffer
Frequently asked questions
- What size storage unit do I need?
- It depends entirely on what you're storing — a 5×5 unit (25 sq ft) suits a few boxes and small items, roughly closet-sized; a 10×10 (100 sq ft) commonly holds the contents of a 1-2 bedroom apartment; a 10×20 or larger typically holds a full house's worth of furniture or a vehicle. Add up your specific items rather than guessing from a general description of your home.
- Why does this calculator add a buffer above my items' actual footprint?
- Because you'll never fill a storage unit's floor space edge to edge in practice — you need aisle space to access items without unloading the entire unit, and stacking is rarely as space-efficient as a flat floor-space sum assumes. A 20% buffer above your items' raw footprint is a reasonable planning margin to avoid renting a unit that's technically big enough on paper but unusable in practice.
- Should I get a drive-up unit or an indoor climate-controlled unit?
- Drive-up units are typically cheaper and offer direct vehicle access for loading, which is convenient for frequent access or bulky items, but they expose contents to more temperature swings. Climate-controlled indoor units cost more but protect temperature-sensitive items (electronics, wood furniture, photos, documents) from extreme heat, cold and humidity — worth the extra cost for anything that could be damaged by those conditions.
- Can I store a vehicle in a standard storage unit?
- It depends on the vehicle and the unit size — a motorcycle fits in even a small unit, while a car typically needs a 10×20 unit at minimum, and many facilities offer dedicated vehicle storage separate from standard units. Confirm size and any facility-specific vehicle storage rules (insurance requirements, running condition) directly with the facility.