Standard Microwave Dimensions
There is no single "standard" microwave size — it depends on the type. Below are the typical width, height, depth, and capacity for each installation type, measured across 696 current models. The number most size charts forget: the ventilation clearance you must add on top.
| Type | Width | Height | Depth | Capacity |
|---|---|---|---|---|
| Countertop Freestanding — sits on the counter | 17.8–21.1" | 10.5–12.8" | 14–18.3" | 0.8–1.3 cu ft |
| Over-the-Range Mounts above the stove, 30" cabinet | 23.9–29.9" | 16.4–17" | 15.3–17.3" | 1.3–1.7 cu ft |
| Built-In Flush in cabinetry, needs a trim kit | 23.4–29.8" | 15.3–19.1" | 16.4–22.4" | 1.2–1.6 cu ft |
| Drawer Pull-out, under the counter or island | 23.5–29.8" | 14.9–15.8" | 23.3–23.6" | 1.2–1.2 cu ft |
Figures are the typical (middle-50%) range across verified current models. Individual models fall outside these ranges in both directions.
Countertop microwaves
The most common type. A typical countertop microwave is about 18–21 inches wide, 11–13 inches tall, and 14–18 inches deep. Capacity runs 0.8–1.3 cu ft — enough for a dinner plate but not a 13×9 casserole. Remember the door swings sideways, so it needs side clearance to open, and the depth on the spec sheet excludes the handle.
Over-the-range (OTR) microwaves
Built to a 30-inch standard width so they align with a 30-inch upper cabinet and the range below. They are usually 16–17 inches tall and 15–17 inches deep. If your cabinet opening is narrower than 30 inches, you need a compact 24-inch OTR model — a standard unit will not fit.
Built-in microwaves
Designed to sit flush in cabinetry with a trim kit. Bodies are typically 23–30 inches wide, but the number that matters is the cabinet cutout, which must be larger than the body to fit the trim kit and clearances. Built-in cutouts are commonly 24, 27, or 30 inches.
Microwave drawers
Pull-out units installed under a counter or in an island. They are wide (24–30 inches) and notably deep (often 23–24 inches) to accommodate the drawer mechanism. Plan the base-cabinet depth accordingly.
Why dimensions alone don't tell you if it fits
Every manufacturer requires open space around the unit for ventilation — commonly around 3 inches at the top and sides and 1–3 inches at the back. A microwave that measures 12 inches tall but needs 3 inches of top clearance really needs a 15-inch gap. That is the single most common reason a microwave "the right size" still doesn't fit. MicrowaveFit adds each model's required clearances automatically — enter your space on any model page or the finder to see what actually fits.
How to measure your space
- Width — measure the opening at its narrowest point; trim and face frames steal width.
- Height — for countertop units, measure counter to the underside of the upper cabinet.
- Depth — measure to the wall, and leave room for the door to open and the handle to clear.
Frequently asked questions
What is the standard size of a countertop microwave?
Most countertop microwaves are about 18–21 inches wide, 10.5–13 inches tall, and 14–18 inches deep, with a 0.8–1.3 cu ft interior. Compact models drop to ~15 inches wide; large families-size units reach 24 inches.
What size is a standard over-the-range microwave?
Over-the-range microwaves are built to a 30-inch standard width so they line up with a 30-inch cabinet and the range below. They are typically 16–17 inches tall and 15–17 inches deep. Narrower 24-inch OTR models exist for smaller cabinet openings.
How much clearance does a microwave need?
Manufacturers require open space around the unit for ventilation — commonly about 3 inches at the top and sides and 1–3 inches at the back for countertop models. Always add this clearance to the physical dimensions before deciding whether a microwave fits, because the spec-sheet size is not the installed size.
Are microwave dimensions the same as the cabinet cutout size?
No. The cutout (the opening in your cabinetry) must be larger than the microwave body to allow for the trim kit and ventilation clearance. Built-in cutouts are commonly 24, 27, or 30 inches wide. Measure the opening, not just the unit.