Free storage unit size calculator. Enter rooms, furniture, and boxes to get the right unit size, from 5x5 to 10x30, with volume estimates.
Your results will appear here.
Enter your values and press Calculate.
Everything you store is converted to cubic feet: a room of furniture counts about 400, a large item 75, a medium item 15, and a box 2. Your total is matched to the smallest standard unit whose capacity covers it, using typical 8-foot ceilings: a 5x5 holds about 200 cubic feet, a 10x10 about 800, a 10x20 about 1,600, and a 10x30 about 2,400.
Storage units are sold by floor size, but what matters is volume. A unit's cubic footage is length × width × height, and most units have 8-foot ceilings, so a 10x10 holds roughly 800 cubic feet.
The calculator converts your inventory to cubic feet with simple planning weights: 400 per room of furniture, 75 per large item like a bed or sofa, 15 per medium item like a chair, and 2 per box. It then picks the smallest standard size with enough capacity, leaving a little breathing room for aisles.
Use this page as your complete storage unit size guide: unlike a generic self storage calculator, it also shows a per-size what-fits chart in the sizes section below.
Count the rooms of furniture you are storing (a studio counts as 1), then add large items, medium items, and boxes separately. Appliances, mattresses, and sofas are large; chairs, nightstands, and small tables are medium.
The result names the recommended size, shows your estimated volume, and lists the unit's floor area and capacity. If you are between sizes, the calculator rounds up: cramming a unit to the ceiling is a false economy.
5x5 (25 sq ft, ~200 cu ft): a closet's worth. Boxes, a small mattress set, seasonal items, dorm room overflow.
5x10 (50 sq ft, ~400 cu ft): a walk-in closet. Studio apartment overflow, one bedroom of furniture, business files.
10x10 (100 sq ft, ~800 cu ft): half a garage. A one-bedroom apartment, a motorcycle, or a small office.
10x15 (150 sq ft, ~1,200 cu ft): a two-bedroom apartment or a compact car.
10x20 (200 sq ft, ~1,600 cu ft): a standard garage. A three-bedroom house or a vehicle with room to spare.
10x30 (300 sq ft, ~2,400 cu ft): a large garage. A four-bedroom house, boats, or business inventory.
As rough planning guides: a studio or dorm usually fits a 5x5 or 5x10. A one-bedroom apartment fits a 10x10. A two-bedroom home needs a 10x15. A three-bedroom home needs a 10x20. A four-bedroom home needs a 10x30.
These assume normally furnished homes. Minimalists can often drop a size; collectors and home offices should go up one. The calculator above beats these rules of thumb because it counts your actual items.
Climate-controlled units cost more but protect against heat, cold, and humidity swings. Choose one for wood furniture, electronics, musical instruments, artwork, photographs, documents, mattresses, and anything leather.
For metal tools, plastic bins, and outdoor gear in mild climates, a standard drive-up unit is usually fine. When in doubt about heirlooms, pay for climate control: humidity damage is permanent.
Disassemble bed frames and tables, stand mattresses and sofas on end, and fill every hollow: drawers, appliances, and suitcases all hold boxes. Stack heavy boxes at the bottom, keep a center aisle so you can reach the back, and put items you will need first near the door.
Measure your largest pieces and the unit's door before moving day. A sofa that will not fit through a 5x5 door turns a cheap unit into an expensive mistake.
Too small means double-handling everything or renting a second unit, which costs more than sizing up in the first place. Too big just costs a little extra per month.
Most facilities let you transfer to a different size, but you pay for the move and the hassle. When torn between two sizes, choose the larger one: the price gap is usually smaller than the cost of being wrong.
The 10x10 is the most rented size: it holds a one-bedroom apartment's worth of belongings (about 800 cubic feet) and suits the widest range of situations.
Convert everything to cubic feet: roughly 400 per room of furniture, 75 per large item, 15 per medium item, 2 per box. Then pick the smallest standard unit whose capacity covers the total.
Most have 8-foot ceilings, which is what capacity figures assume. Some facilities offer taller units: always confirm ceiling height when comparing capacities.
Usually a 5x10. A lightly furnished studio can fit a 5x5, and a packed one may need a 10x10. Count your actual items in the calculator above for a precise answer.
A 10x10 (about 800 cubic feet) is the standard recommendation for a one-bedroom apartment.
A 10x15 (about 1,200 cubic feet) typically holds a two-bedroom apartment's furnishings.
A 10x20 (about 1,600 cubic feet), roughly a standard one-car garage, fits most three-bedroom homes.
Yes, in a 10x20 or larger, provided the facility allows vehicles and the door is wide enough. Measure the car and the door, and check the facility's vehicle policy first.
Most facilities let you move to another unit, but you will pay for the extra labor. Sizing up slightly at the start is cheaper than renting a second unit later.
Usually yes, subject to availability. Ask about transfer fees and whether your rate is guaranteed on the new unit before you commit.
Get it for wood furniture, electronics, instruments, artwork, photos, documents, and mattresses. Skip it for tools and outdoor gear in mild climates.
25 square feet of floor space, about 200 cubic feet with 8-foot ceilings: roughly a large closet. Good for boxes, a mattress set, and seasonal items.