No, over-the-range microwaves are not all the same size, though most are standardized to fit a 30-inch wide cabinet opening. Heights and depths vary significantly between models, requiring precise measurement of your backsplash clearance and cabinet depth before installation.
You might think replacing a kitchen appliance is as simple as swapping the old unit for a new one. With microwaves mounted above the stove, that assumption often leads to frustration. A new model might stick out too far, hang too low, or refuse to mount on the existing wall plate.
Standardization exists, but only to a point. While the width is usually consistent, the other dimensions fluctuate based on capacity, brand, and design style.
Ignoring these variances creates safety hazards or installation failures. You need to know exactly which numbers match your current setup and which ones offer wiggle room.
The Standard Width Rule For Most Homes
The vast majority of over-the-range (OTR) microwaves fall into the 30-inch width category. This does not mean the unit itself is exactly 30 inches wide.
Manufacturers build these units to fit into a standard 30-inch cabinet opening. The actual physical width of the appliance typically measures around 29.875 inches (or 29 7/8 inches). This slight reduction allows the door to swing open without binding against the adjacent cabinetry.
If your cabinets are the standard width, you have many options. If you have a custom kitchen with a 36-inch opening, you face a different challenge. You will either need a specifically designed 36-inch microwave (which are rare and expensive) or a standard 30-inch unit with a “filler kit” to close the gaps on the sides.
Are All Over The Range Microwaves The Same Size? Truth About Dimensions
While width is generally consistent, height and depth prevent these appliances from being universal. “Are All Over The Range Microwaves The Same Size?” is a question that usually arises when a homeowner realizes their new unit hangs dangerously close to the stove burners.
Design trends have shifted over the last decade. Older units were often compact and short. Modern units tend to offer larger interior capacities, which forces the exterior casing to grow taller and deeper.
The table below breaks down the variances you will encounter when shopping for a replacement.
Microwave Dimension Categories
| Dimension Type | Typical Measurement Range | Why This Number Matters |
|---|---|---|
| Standard Width | 29.8″ – 29.9″ | Fits the standard 30-inch cabinet opening found in most homes. |
| Standard Height | 15″ – 17″ | Determines clearance above the stovetop; taller units reduce workspace. |
| Low Profile Height | 10″ – 11″ | Designed to replace range hoods without losing vertical cooking space. |
| Standard Depth | 15″ – 18″ (excluding handle) | A deeper unit may stick out past your upper cabinets, affecting aesthetics. |
| Open Door Depth | 38″ – 42″ | Ensures you can fully open the microwave without hitting an island or wall. |
| Internal Capacity | 1.6 – 2.2 cubic feet | Larger capacity usually equals a taller exterior unit. |
| Weight | 50 – 65 lbs | Heavier units may require reinforced cabinet support bolts. |
Why Height Is The Critical Safety Factor
Height creates the most headaches during installation. If you replace an old, shorter microwave with a modern, tall one, you lose space between the bottom of the microwave and the surface of your range.
Building codes and manufacturer instructions dictate minimum clearances. Generally, you need at least 30 inches from the bottom of the upper cabinet to the stove surface before installing the microwave. Once installed, there should be roughly 13.5 to 16 inches of clearance between the microwave bottom and the cooktop.
If your new microwave is 17 inches tall and your old one was 15 inches, you lose two inches of clearance. This makes it difficult to stir tall pots and increases the risk of the microwave handle getting too hot. Always measure your current vertical space before buying.
Depth Considerations And Cabinet Flushness
Microwaves are not flush with upper cabinets. Standard upper cabinets are 12 inches deep. Over-the-range microwaves average 15 to 16 inches in depth, meaning they will protrude 3 to 4 inches beyond the cabinet face.
This protrusion serves a purpose. It allows the venting system (located on the top front or bottom) to capture steam and smoke from the front burners of the stove. If the microwave were flush with the cabinets, the ventilation capture rate would drop effectively to zero.
However, some high-capacity models push this depth to 18 inches. In a small kitchen, a unit sticking out that far can feel imposing and might block your view of the rear burners.
The Mounting Plate Complication
Many homeowners assume they can reuse the metal mounting bracket screwed into the wall from the previous microwave. This is almost never the case.
Manufacturers change the hook placement, bolt width, and exhaust location frequently. Even if you stay with the same brand, a model from five years ago will likely use a different bracket than the current version.
According to GE Appliances installation guidance, mounting brackets are not interchangeable between different models or brands. You must remove the old hardware and install the new plate included in the box. This often requires drilling new toggle bolt holes in the drywall, so be prepared for some minor wall repair.
Capacity Vs. Exterior Size
Do not confuse internal capacity with external dimensions. A 1.7 cubic foot microwave and a 1.9 cubic foot microwave might have identical width and height, with the difference coming from internal component arrangement or a slightly deeper casing.
Conversely, a 2.1 cubic foot model will almost certainly be taller. If you want maximum internal space, verify that your cabinetry allows for a unit that hangs lower. If you cook with tall stockpots often, you might prefer a smaller capacity unit to preserve that vertical clearance.
Low Profile Models: A Specific Solution
If your upper cabinets are mounted low, a standard over-the-range microwave might violate safety clearances. In this scenario, Low Profile microwaves are the answer.
These units measure only about 10.3 inches in height compared to the standard 16+ inches. They fit in the same 30-inch wide opening but leave much more room above the stove. They usually cost more than standard units but save you the expense of remodeling your cabinetry.
Comparison of Popular Models
To illustrate the variety in “standard” sizes, look at the specifications of common units available today. While widths stay close to the 30-inch mark, height and depth fluctuate enough to ruin an installation plan.
The following table compares actual physical dimensions of top-selling units.
Size Variations By Model
| Model Example | Width | Height | Depth |
|---|---|---|---|
| Whirlpool Low Profile (WML55011) | 29.88″ | 10.31″ | 18.00″ |
| GE Standard (JVM3160) | 29.88″ | 16.50″ | 15.25″ |
| Samsung Bespoke (ME21B706) | 29.88″ | 17.06″ | 16.50″ |
| LG ExtendVent (LMV2031) | 29.88″ | 16.44″ | 15.88″ |
| Sharp Carousel (R-1874) | 29.94″ | 16.38″ | 15.28″ |
| Bosch 800 Series | 29.94″ | 17.50″ | 15.75″ |
Venting Direction Affects Installation Space
Dimensions are not just about the metal box. You must account for the venting path. Over-the-range microwaves can vent in three ways: outside through the roof, outside through the wall, or recirculating back into the room.
If you vent through the wall directly behind the unit, the ductwork placement must align perfectly with the blower outlet on the microwave. If the new microwave’s outlet is an inch higher or lower than the old one, you might have to cut a new hole in your house wall or adjust the ducting.
Recirculating installs are easier as they vent out the front grille. However, they require a charcoal filter that needs regular replacement to keep odors down.
What About 36-Inch Models?
Years ago, 36-inch wide microwaves were more common. Today, they are rare. If you have a 36-inch opening, you have two choices.
First, you can hunt for one of the few 36-inch models still in production. These are often high-end, commercial-style units with price tags to match.
Second, and more commonly, you buy a standard 30-inch microwave and purchase a side filler kit (sometimes called a trim kit) from the manufacturer. These metal strips screw into the side of the microwave or the cabinet to cover the 3-inch gap on either side. This creates a finished look while using a standard, affordable appliance.
Measuring For A Perfect Fit
Do not rely on the specs found online alone. Physical variables in your kitchen, like tile backsplash thickness or cabinet warping, change the math.
Step 1: Width Check
Measure the opening width at the front and the back. Cabinets can bow over time. If the back is narrower than 29.8 inches, a new unit might not slide all the way in.
Step 2: Vertical Clearance
Measure from the top of the stove to the bottom of the upper cabinet. Subtract the height of the new microwave you want to buy. The remaining number is your workspace clearance. If that number is less than 13 inches, consider a low-profile model.
Step 3: Depth And Door Swing
Check adjacent walls. If your microwave is next to a deeper pantry cabinet or a wall, a deep microwave door might hit it when opening. Most hinges require zero clearance to open to 90 degrees, but you need more space to open the door fully for cleaning.
The “Bump Out” Kit Option
Sometimes, homeowners with 15-inch deep upper cabinets (deeper than standard) run into trouble. A standard microwave is practically swallowed by deep cabinets, preventing the door from opening or the vent from working.
In this specific case, you need a “bump out” kit. This bracket assembly pushes the microwave forward, away from the wall, so the door sits proud of the cabinetry. It requires secure fastening to studs since the leverage on the wall bracket increases significantly.
Electrical Requirements
Size isn’t just physical dimensions; it’s also electrical capacity. Most OTR microwaves require a dedicated 15-amp or 20-amp circuit. If you upgrade from an older, lower-wattage unit to a high-powered 1100-watt model, you might trip the breaker if other kitchen lights share that circuit.
Check the plug orientation as well. Some cords have flat plugs that fit behind the unit; others have standard plugs that require the outlet to be recessed in the upper cabinet. If the outlet is in the cabinet above, you will need to drill a hole for the power cord to pass through.
Final Fit Checklist Before Ordering
Buying an appliance online is convenient, but returns are a hassle due to the weight of these units. Run through this quick list to confirm your choice matches your kitchen.
- Opening Width: Is it a standard 30-inch space? If 36 inches, did you order a filler kit?
- Backsplash Height: Does the tile go all the way up? If not, a shorter microwave might expose untiled drywall.
- Cabinet Depth: Are your cabinets standard 12-inch depth? If deeper, you need a spacer kit.
- Venting Strategy: Did you check if the blower motor can be rotated to match your external vent?
- Bracket Needs: Are you prepared to remove the old bracket and drill new holes?
The answer to “Are All Over The Range Microwaves The Same Size?” is clearly no. While the 30-inch width standard makes shopping easier, the variations in height and depth dictate the success of your project. Focusing on the vertical clearance and the mounting hardware ensures your new kitchen upgrade functions safely and looks great.