Most countertop microwaves measure about 16 to 20 inches deep with the door closed, over-the-range models about 15 to 18 inches, and built-in microwaves about 20 to 25 inches.
A tape measure run across the front of the cabinet is the easy way to end up with a microwave that fits on paper and not in your kitchen. Depth is where that plan falls apart, because the number on the box rarely matches the space you actually need once the door swings open.
The shorthand above holds for the vast majority of US models, but the exact figure depends on the type of unit you’re buying. Below are the typical ranges by category, how to measure so you don’t get burned, and the two mistakes that cause most fit problems.
How Deep Are Standard Microwaves by Type?
Depth varies more by microwave type than by brand, and the ranges below cover what you’ll find in most showrooms today.
Countertop models are the widest category. Compact units often run about 12 to 16 inches deep, while standard and large countertop microwaves land closer to 16 to 20 inches. That difference matters when your counter is shallow or sits beside a wall.
Over-the-range microwaves are built to sit above your cooktop, so they tend to stay shallower, usually 15 to 18 inches with the door closed. Low-profile over-the-range models go even smaller, with one manufacturer guide listing roughly 18 inches deep and 10 inches high.
Built-in microwaves are the deepest because they need to sit flush inside cabinetry. Most fall between 20 and 25 inches.
| Microwave Type | Typical Depth (Door Closed) | Best For |
|---|---|---|
| Compact countertop | 12–16 inches | Small kitchens and tight counters |
| Standard countertop | 16–20 inches | Everyday home use |
| Over-the-range | 15–18 inches | Cooking above a stove |
| Low-profile over-the-range | About 18 inches | Low cabinets above the cooktop |
| Built-in | 20–25 inches | Flush cabinet installation |
How Do You Measure Microwave Depth Correctly?
Measure from the front of the microwave to the back with the door closed — that single rule prevents most sizing errors.
KitchenAid’s sizing guide and Home Depot’s measuring instructions both treat door-closed depth as the working number for countertop placement. If you’re installing a built-in or over-the-range unit, you also need the cutout measurements, since the microwave has to fit the opening in your cabinetry, not just the space in front of it.
Then plan for the door. A closed unit that measures 18 inches can need two feet or more of open air once the door swings out, and over-the-range models vary widely depending on how the hinge and vent are built. Measure the clearance in front of the microwave before you buy, especially if it faces a refrigerator or a walkway.
For over-the-range installations, one appliance-sizing guide recommends planning at least 30 inches between the cooktop and the bottom of the microwave unless the specific model is rated for less. That clearance protects both your cooking space and the unit itself.
If you’re hunting for a shallow model to fit a specific cabinet, a tested roundup of 12 inch deep microwave options is worth a look before you start comparing spec sheets.
What Are the Most Common Microwave Depth Mistakes?
Two errors cause nearly every microwave fit problem, and both come from trusting the wrong number.
The first is measuring only the cabinet opening or the body of the unit and ignoring door-open depth. A microwave that clears the wall by an inch may still hit the counter when you pull the door open. Maytag’s microwave sizing guide flags this exact gap between closed and open dimensions.
The second is confusing external depth with internal capacity. Two microwaves can both measure 19 inches deep and hold very different volumes inside, because the housing, turntable, and venting eat up space differently. If capacity is what you actually care about, check the cubic feet rating, not the depth.
One more thing worth knowing: “standard” isn’t a universal number. It changes by type, so a 17-inch countertop unit and a 17-inch over-the-range unit won’t sit the same way in your kitchen.
Quick Depth Reference Before You Buy
Match the depth range to your space first, then confirm the door swing, then check capacity.
- Countertop, compact: 12–16 inches deep — best for small counters.
- Countertop, standard: 16–20 inches deep — the most common home size.
- Over-the-range: 15–18 inches closed — plan for the door and hood clearance.
- Built-in: 20–25 inches deep — measure the cutout, not just the front.
Bring a tape measure to the store, measure from the wall to the front edge of your counter, and subtract two inches for breathing room. That leaves you a real number to compare against the specs.
FAQs
Does microwave depth include the door handle?
Most depth specs measure the body of the unit with the door closed, and handles usually add an inch or less. If your clearance is tight, measure your specific model to be safe. Manufacturer spec sheets list the exact external depth, so check those rather than relying on the general ranges.
Can a deep microwave fit in a shallow cabinet?
Only if the unit is designed for that opening. Built-in microwaves need their full 20 to 25 inches plus the cutout dimensions to sit flush. Putting a standard-depth microwave inside a shallow cabinet usually leaves the front protruding, which blocks doors and looks uneven.
Is depth the same as capacity?
No. Depth is an outside measurement, while capacity is the internal volume in cubic feet. Two microwaves with the same depth can hold different amounts inside, because interior layout and turntable size vary. Compare cubic feet ratings if usable space is what matters to you.
References & Sources
- Maytag. “Microwave Sizes: A Guide to Common Dimensions” Source for standard depth ranges and door-open measurement warnings.
- KitchenAid. “Microwave Sizes: How to Measure a Microwave” Source for correct depth-measuring method and cutout guidance.
- Home Depot. “How to Measure Microwaves: Sizes & Tips” Source for clearance planning and measuring steps.
