How to Choose the Right Microwave Size for Your Kitchen

Here's a question: when did buying a microwave become so complicated? I've spent the past three weeks with six different microwaves cluttering my kitchen—ranging from a tiny 17-litre unit that couldn't fit a dinner plate to a 32-litre beast that dominated the worktop like it owned the place. The verdict? Size matters more than you'd think. And getting it wrong is surprisingly easy.

Whether you're replacing an old microwave, kitting out a new flat, or simply wondering if your current model is actually the right fit, this guide covers everything you need to know about choosing the right microwave size for your UK kitchen.

Understanding Microwave Capacity: What the Litres Actually Mean

Microwave capacity is measured in litres, and this single number probably matters more than any other specification. But here's what manufacturers don't tell you: the stated capacity and the usable space are two different things entirely.

The Size Categories Explained

Microwaves fall into four broad size categories:

Small/Compact (15-20 litres)

These compact microwaves work well for individuals, couples, or anyone with limited counter space. A 17-litre microwave will typically accommodate a standard 25cm dinner plate—though just barely. The Abode range, for instance, offers several 20-litre models that strike a reasonable balance between compact dimensions and practical usability.

Medium (20-25 litres)

The sweet spot for most households. A 23-litre microwave comfortably fits standard dinner plates and medium casserole dishes. If you're cooking for one or two people and primarily reheating meals or making simple dishes, this size will serve you well.

Large (25-32 litres)

Family-sized territory. These microwaves can handle larger dishes, multiple items, and bigger portions. The turntable diameter typically exceeds 30cm, meaning full-sized plates fit without awkward angling.

Extra Large (32+ litres)

Primarily combination microwaves with convection and grill functions. Frankly, if you're looking at this size, you're probably treating your microwave as a secondary oven—which some people absolutely do.

The Turntable Problem

Here's something I wish I'd known before testing: interior capacity doesn't tell you whether your favourite casserole dish will actually fit. The turntable diameter and interior height matter just as much—arguably more.

For a microwave that handles standard dinner plates without drama, you want:

• Turntable diameter: at least 27cm (30cm+ for larger plates)
• Interior height: minimum 20cm for bowls and covered dishes

I tested a 25-litre microwave that, on paper, should have been spacious. In practice, the shallow interior meant anything taller than a cereal bowl scraped against the roof. Frustrating doesn't begin to cover it.

External Dimensions: Will It Actually Fit?

Before falling in love with a microwave based on features or price, measure your intended space. Then measure it again. I've seen too many returns due to the classic "it looked smaller online" scenario.

Standard Size Ranges

Compact microwaves:

• Width: 40-45cm
• Depth: 30-35cm
• Height: 25-30cm

Standard microwaves:

• Width: 50-55cm
• Depth: 40-45cm
• Height: 30-35cm

Large/Combination microwaves:

• Width: 55-60cm
• Depth: 45-55cm
• Height: 35-45cm

The Ventilation Factor

This catches people out constantly. Microwaves need breathing room—you can't just wedge them into a tight space and hope for the best.

Allow for:

• 5cm clearance on each side
• 10-15cm clearance above
• Some airflow at the back

I once squeezed a microwave into a shelf unit without proper ventilation. It overheated within a month. Lesson learned.

Microwave Wattage: How Much Power Do You Actually Need?

Wattage determines cooking speed and, to some extent, cooking quality. Higher wattage means faster heating. But more isn't always better—particularly if you're working with limited electricity capacity or want to save on energy bills.

The Wattage Scale

600-700 watts

Entry-level. Suitable for basic reheating and defrosting, but cooking times are noticeably longer. Common in very compact models and low-wattage microwaves designed for caravans and boats.

700-800 watts

The budget standard. Most affordable small microwaves sit here. Perfectly adequate for everyday use—reheating leftovers, making porridge, defrosting meat. Just don't expect restaurant-speed results.

800-900 watts

The practical middle ground. This is what I recommend for most households. Cooks reasonably quickly, handles most tasks efficiently, and won't send your electricity bill through the roof.

900-1000 watts

Powerful enough for proper cooking, not just reheating. If you use your microwave for more than ping meals—steaming vegetables, cooking rice, making sauces—this range makes a noticeable difference.

1000+ watts

Premium territory. Cooks fast and evenly. Essential for combination microwaves that need extra power for grilling and convection functions.

My Honest Take on Wattage

After testing microwaves across the power spectrum, here's what surprised me: the difference between 700W and 900W is more significant than I expected. A jacket potato that takes 12 minutes in a 700W microwave cooks in about 8 minutes at 900W. Over a week of daily use, that time adds up.

But—and this is important—if you're primarily reheating yesterday's curry or making beans on toast, you genuinely won't notice. Save your money and put it toward other features that matter more to your actual cooking habits.

Types of Microwaves: Finding Your Match

Not all microwaves are created equal, and the type you choose affects both size and functionality.

Solo (Standard) Microwaves

The classic. Does microwave things: reheats, defrosts, cooks with microwave energy. Nothing fancy, nothing complicated. If you just want to heat food quickly, this is all you need.

Solo microwaves tend to be the smallest option, making them ideal for kitchen spaces where counter real estate is precious.

Grill Microwaves

Adds a heating element for browning and crisping. Can toast cheese on top of dishes, give sausages a bit of colour, and generally make microwave meals look less... microwaved.

Slightly larger than solo models due to the grill element. Worth considering if you find standard microwave results a bit pale and unappetising.

Combination (Combi) Microwaves

The kitchen multitasker. Combines microwave, grill, and convection oven functions. Can genuinely roast a chicken, bake a cake, and do everything a regular microwave does.

The trade-off? Size. Combi microwaves are significantly larger—often measuring 55-60cm wide. They need more ventilation space and dominate worktops in smaller kitchens. I tested one for a month and, honestly, it felt like having a small oven parked on my counter.

Flatbed Microwaves

Worth a mention: these lack a turntable entirely. Instead, the microwave energy distributes from beneath a flat cooking surface. The advantage? Square and rectangular dishes fit without the constant "will it spin without hitting the walls" calculation.

If you regularly use casserole dishes or baking trays, flatbed models offer notably more usable space than their turntable equivalents.

Matching Microwave Size to Your Household

This is where practical reality meets marketing claims. Let me break down what actually works for different situations.

For Students and Small Flats

A 17-20 litre solo microwave with 700-800W is genuinely all you need. Compact enough to fit in limited spaces, capable enough for student cooking basics.

The Abode 20L range hits this brief well—affordable, functional, fits standard plates, doesn't try to be anything it isn't.

For Couples and Small Families (2-3 people)

The 20-25 litre range at 800-900W. Large enough for family dinner plates, powerful enough to cook reasonably quickly, small enough to not dominate the kitchen.

For Larger Families (4+ people)

27-32 litres becomes practical necessity rather than luxury. A larger turntable means cooking for multiple people doesn't require doing everything in batches.

At this size, consider whether a combination microwave makes sense. The extra functionality can reduce reliance on a full-sized oven for many family meals.

For Caravans, Boats, and Holiday Homes

Low wattage microwaves—typically 500-700W—designed for limited power supplies. Size usually maxes out around 17 litres. The very small microwave for caravan category has specific options worth investigating.

The Space Audit: Measuring Before You Buy

Right. Let's get practical. Before ordering anything, measure these three things:

1. Your available space

Width, depth, and height—including ventilation allowances. Write it down. Then check it matches the microwave specifications before clicking "buy."

2. Your largest plate

Seriously. Get a tape measure to your dinner plates. A 28cm plate won't fit in a microwave with a 25cm turntable, regardless of what the interior capacity suggests.

3. Your most-used dish

That casserole dish you use three times a week? Measure it. That's your real-world size requirement.

I cannot stress this enough: the number of people who buy microwaves only to discover their everyday dishes don't fit is genuinely surprising. Don't be that person.

Built-In vs Freestanding: A Size Consideration

Choosing between built-in and freestanding microwaves affects your size options significantly.

Freestanding Microwaves

Maximum flexibility. Put them anywhere with a power socket and sufficient ventilation. Move them if your kitchen layout changes. Generally more affordable for equivalent specifications.

The downside? They take up worktop space. In a small kitchen, that trade-off can feel significant.

Built-In Microwaves

Integrated into cabinetry, typically at eye level or within a housing unit. Frees up worktop space and looks sleeker. Standard built-in widths hover around 60cm to match standard cabinet dimensions.

The catch? More expensive, require installation, and if your cabinets aren't standard dimensions, compatibility becomes complicated.

Price vs Size: What to Expect

Generally speaking:

• 17-20L solo microwaves: £40-80
• 20-25L solo microwaves: £60-120
• 25-32L solo/grill microwaves: £100-200
• Combination microwaves: £150-400+

Brands like Abode offer solid value at the budget end, while premium brands like Panasonic and Samsung command higher prices for equivalent sizes—though often with better build quality and longer warranties.

My advice? Unless you're a serious home cook or need specific features, mid-range models offer the best balance. I've tested budget microwaves that work perfectly well for years and premium models that didn't justify the price premium for typical household use.

Common Mistakes to Avoid

1. Focusing only on capacity

Litre figures mean nothing if the turntable can't fit your plates. Interior dimensions matter more than total capacity.

2. Ignoring ventilation requirements

Microwaves need airflow. Planning to put one in a closed cabinet? Reconsider.

3. Overbuying on wattage

Unless you genuinely need rapid cooking, 800-900W handles most tasks. The extra cost and energy consumption of higher wattage isn't always justified.

4. Underestimating combination microwave size

They're big. Really big. If your kitchen is compact, a combi might not be practical regardless of how appealing the functionality sounds.

5. Not measuring first

Measure twice, buy once. Or learn the hard way. Your choice.

The Verdict: My Recommended Approach

After weeks of testing and far too many jacket potatoes, here's what I'd suggest:

For most UK households, a 20-25 litre microwave with 800-900W represents the sweet spot. Large enough to handle everyday cooking, powerful enough to work efficiently, compact enough to fit standard kitchen spaces.

If you're cooking for a larger family or want flexibility to replace some oven use, step up to 27-32 litres with 900W+—but only if your worktop can accommodate it.

And if you're tight on space or cooking for one? A 17-20 litre compact model like those in the Abode range does the job without demanding prime kitchen real estate.

The right microwave is the one that fits your space, handles your actual cooking needs, and doesn't make you want to hurl it out the window because your favourite bowl doesn't fit inside. Choose accordingly.