Storage unit size planner
Pick what you are storing and get a starting size, its floor area and a scale drawing. Then check your longest item against it.
How the suggestion is made
Public Storage's help center describes its most popular sizes as 5x10 (one room), 10x10 (three rooms) and 10x20 (five rooms). Its Dallas page says a 10x20 holds a standard sedan or small-to-midsize SUV and 10x25 or 10x30 units fit large pickups, large SUVs and cargo vans. Those are the published anchors. The 10x15 step for four rooms is our interpolation, and the 5x5 for boxes is simple arithmetic: half the floor of a 5x10.
| Size | Floor area | Rule of thumb | Basis |
|---|---|---|---|
| 5x5 | 25 sq ft | Half the floor area of a 5x10: boxes, seasonal items, a few small pieces. | Arithmetic |
| 5x10 | 50 sq ft | About one room of furniture and boxes. | Published operator guidance |
| 10x10 | 100 sq ft | About three rooms. | Published operator guidance |
| 10x15 | 150 sq ft | Between the three-room and five-room sizes (about four rooms). | Our interpolation |
| 10x20 | 200 sq ft | About five rooms, or a standard sedan or small-to-midsize SUV. | Published operator guidance |
| 10x30 | 300 sq ft | Large pickups, large SUVs and cargo vans; or more than five rooms. | Published operator guidance |
Rooms vary a lot, so treat this as a starting point. If you are between sizes, price both in the calculator before deciding.
Measure before you reserve
- Door opening: it is narrower and lower than the unit itself. Check sofas, mattresses and tall furniture against it.
- Longest item: it must fit along the longest wall, or diagonally if you can angle it.
- Actual dimensions: Public Storage's terms note that "actual unit sizes may vary from approximate size estimate". Ask for the real measurements.
- Access aisle: leave a path to the back if you will need things during your stay.
Sources: Public Storage, Choose a Unit Size and Dallas storage page, both checked 22 October 2026.