Buying guide
Standard Interior Door Sizes
Picking the right size is the first step to a door that fits and swings correctly. Below are the standard interior door widths, heights, and rough-opening dimensions used across the U.S., plus how to measure a slab replacement or a framed opening. All Designer Doors Supply doors are also available in custom sizes.
Standard interior door widths
Interior door widths are given in inches, for a standard 80″ (6′8″) height.
| Nominal | Width | Typical use |
|---|---|---|
| 1′6″ | 18″ | Small closets, cabinets |
| 2′0″ | 24″ | Closets, small bathrooms, pantries |
| 2′4″ | 28″ | Bathrooms, secondary rooms |
| 2′6″ | 30″ | Bedrooms, bathrooms (very common) |
| 2′8″ | 32″ | Bedrooms, main rooms; ADA-friendly clearance |
| 3′0″ | 36″ | Main entries, accessible passage, wide rooms |
Heights & thickness
- Standard height: 80″ (6′8″)
- Tall option: 96″ (8′0″)
- Typical slab thickness: 1⅜″ for interior doors
Taller and nonstandard heights are available as custom orders.
Rough opening (pre-hung)
A rough opening is the framed opening before trim. As a rule, add about 2″ to the door width and about 2½″ to the height.
| Door width | Rough opening width |
|---|---|
| 24″ | ≈ 26″ |
| 28″ | ≈ 30″ |
| 30″ | ≈ 32″ |
| 32″ | ≈ 34″ |
| 36″ | ≈ 38″ |
For an 80″ door, frame the rough opening height at about 82½″ from the finished floor.
Door configurations at a glance
The configuration affects how the door opens and how you measure the opening. Tap a type to shop it.
Closet door sizes (bi-fold & bypass)
Closet doors are sized to the finished opening. Common opening widths:
| Configuration | Common opening widths | Height |
|---|---|---|
| Bi-fold (single/pair) | 24″, 30″, 32″, 36″, 48″, 60″, 72″ | 80″ (96″ tall) |
| Bypass (sliding) | 48″, 60″, 72″, 96″ | 80″ (96″ tall) |
Pocket door sizes
A pocket door needs wall space for the door to slide into. Frame the rough opening at roughly twice the door width plus 1″.
- 28″ door → ≈ 57″ rough opening
- 30″ door → ≈ 61″ rough opening
- 32″ door → ≈ 65″ rough opening
- 36″ door → ≈ 73″ rough opening
How to measure
Replacing the slab only
Measure the existing door’s width and height in three places and use the largest reading; note the thickness. Match to the nearest standard size, or order a custom slab.
Replacing the whole unit (rough opening)
- Measure the width between the framing studs.
- Measure the height from the subfloor to the top framing member.
- Measure the wall thickness (for the jamb).
- Send the measurements to our team — we’ll confirm the correct door system.
Not sure which size fits? Contact our specialists and we’ll help you match it.
Door size FAQ
What is the standard interior door size?
The most common interior door size is 30 inches wide by 80 inches (6 ft 8 in) tall, with 32 and 36 inches also widely used. Standard slab thickness is 1 3/8 inches.
What size rough opening do I need for a 30-inch door?
For a 30-inch prehung door, frame the rough opening about 32 inches wide and roughly 82 1/2 inches tall from the finished floor — about 2 inches wider and 2 1/2 inches taller than the door.
What is the standard interior door height?
The standard interior door height is 80 inches (6 ft 8 in). An 8-foot (96-inch) tall option is also available for taller rooms.
Can I order custom door sizes?
Yes. All of our interior and exterior doors are available in custom widths, heights, and 8-foot tall options to fit nonstandard openings.