Most people need a 5x10 for a studio or one-bedroom, a 10x10 for about three rooms, and a 10x20 for a larger home or one car.
The 10x10 is the most popular size. If you are unsure between two sizes, measure your largest pieces first. They decide the size more than the number of boxes does.
Storage unit sizes at a glance
Unit sizes are width by depth in feet. A 10x10 is 10 feet wide and 10 feet deep, or 100 square feet of floor.
| Size | Floor area | Compares to | Fits | Avg. monthly |
|---|---|---|---|---|
| 5x5 | 25 sq ft | A large closet | Seasonal clothes and decor, documents, a dorm's worth of summer storage. No large furniture. | $34.89 |
| 5x10 | 50 sq ft | A walk-in closet | A queen mattress, dresser, nightstands, TV, a couch or chair, bikes and tools. | $50.92 |
| 10x10 | 100 sq ft | Half a one-car garage | About three rooms: a king mattress, living room set, large appliances, tables. | $80.43 |
| 10x15 | 150 sq ft | A large bedroom | A two-bedroom home's furniture plus boxes. | $109.03 |
| 10x20 | 200 sq ft | A one-car garage | Up to four bedrooms of furniture, a piano, or one car. | $130.14 |
| 10x30 | 300 sq ft | About a 1.5-car garage | An entire household. | Varies |
Prices are 2026 national averages for units booked online. There is no separate national average for a 10x30.
How to pick the right size in four steps
- List the big pieces. Mattresses, sofas, dressers, appliances and anything long, like a headboard or a kayak. These set the floor plan.
- Measure the longest item. A sofa longer than 5 feet rules out the narrow side of a 5x10 if it has to lie flat.
- Plan to stack. Units are usually tall enough to stack boxes well above head height. Floor area matters more than height for furniture.
- Leave an aisle if you will visit. If you need things back during the rental, leave a path to the back. That can mean the next size up.
By situation
| Your situation | Start with |
|---|---|
| College student over the summer | 5x5 or 5x10 |
| Studio or one-bedroom move | 5x10 |
| Two-bedroom apartment | 10x10 or 10x15 |
| Three-bedroom house | 10x15 or 10x20 |
| Home renovation, a few rooms at a time | 10x10 |
| Storing a car | 10x20 drive-up. See car storage. |
| Business inventory or tools | Depends on shelving; a 5x10 with shelves holds a lot |
Tip: per square foot, bigger units are cheaper. A 10x10 averages $0.80 per square foot against $1.40 for a 5x5. If you are on the edge, the larger unit may cost less than you expect. Our cost guide has the full breakdown.
Common questions
How big is a 10x10 storage unit?
100 square feet, about half a one-car garage. It holds roughly three rooms of furniture, including a king mattress and a living room set.
How big is a 5x10 storage unit?
50 square feet, similar to a walk-in closet. It fits the contents of a studio or one-bedroom apartment.
Can a car fit in a 10x20 storage unit?
Yes, most cars and small trucks fit in a 10x20, which is about the size of a one-car garage. The facility has to allow vehicles in that unit.