Dishwasher Rough Opening: The Cabinet Cutout Size
A standard built-in dishwasher needs a cabinet opening of 24″ wide × 34½″ tall × 24″ deep. The machine itself is built slightly under that so it slides in — the number that matters for your cabinets is the opening, not the appliance.
Standard dishwasher rough opening
| Dimension | Rough opening | Why |
|---|---|---|
| Width | 24″ | Machine is ~23¾″ so it slides into a clean 24″. |
| Height | 34–34½″ | Fits under a 36″ counter; legs adjust to fill it. |
| Depth | 24″ | Matches a standard base cabinet run. |
An 18″ compact dishwasher uses the same logic with an 18″ opening. The depth and height don’t change — only the width. Which one your kitchen is built for comes down to the gap left in the cabinet run; see 18″ vs 24″ dishwashers.
The three measurements, and the gotchas
Width (24″). Measure the actual gap between the cabinet boxes, not nominal — older or out-of-square cabinets can leave 23½″ or 24¼″, and a hair under 24″ means shaving a filler strip.
Height (34–34½″). Measure floor-to-underside-of-counter at the front. The dishwasher rides on adjustable leveling legs that extend from about 33½″ to 34½″, so it can fill the opening and meet the counter.
Depth (24″). The body is ~24″; the door adds a couple inches when closed (the control panel and handle) and swings down ~21″ into the room when open.
The raised-floor trap
If tile or LVP was added after the cabinets, the floor-to-counter height can drop below the dishwasher’s minimum — sealing it in so it can’t be removed for service. Always measure the finished floor-to-counter height before buying.
Plumbing and electrical rough-in
The opening also needs the connections waiting in it. Standard practice puts the water supply, drain and electrical in the lower-left rear corner (as you face the opening), with a 1½″ access hole drilled into the adjacent sink cabinet for the supply line and drain hose. Confirm the location against your model’s install sheet — it’s the authority.
Frequently asked
What size opening does a dishwasher need?
Will a 24-inch dishwasher fit a 24-inch cabinet opening?
How tall is the dishwasher opening?
Where do the water and drain lines go?
Measured from official ENERGY STAR data + manufacturer spec sheets · Last verified June 2026