Mattress Measurements: Complete Canadian Guide to All Three Dimensions

11 min read

Mattress measurements are the width, length, and depth of a mattress, and all three decide whether a bed fits your body, your room, your sheets, and your front door. Mattress Miracle has fitted Brantford families for these numbers since 1997, and our founder has spent 40+ years in the mattress industry watching shoppers focus on the size label (Twin, Queen, King) while overlooking depth. A standard Queen measures 60 inches by 80 inches (152 x 203 cm). A standard King is 76 inches by 80 inches (193 x 203 cm), 16 inches wider than a Queen and the same footprint as two Twin XL mattresses side by side. Canadian and American mattress sizes match exactly, so any North American brand fits standard Canadian frames and accessories.

Depth is the dimension most people skip. A modern mattress can run from 8 inches on a basic model to 15 inches on a flagship hybrid, and that 7-inch swing changes your sheets, your bed frame fit, and how easily you climb in and out. The team at Mattress Miracle on West Street in Brantford checks all three numbers before a customer buys, because depth is what most often surprises people on delivery day.

Why All Three Mattress Measurements Matter

Most mattress shopping guides only discuss width and length. That is a problem. The depth (or thickness) of a modern mattress can range from 8 inches on a basic model to over 15 inches on a flagship hybrid. That difference of 7 or more inches has real consequences for your bed frame, your sheets, your bedroom aesthetics, and your ability to get in and out of bed comfortably.

Width and length determine whether you and your partner (or your growing teenager) have enough room to sleep without hanging off the edge. Depth determines how much cushioning and support material sits between you and the base of the mattress, which directly affects comfort, durability, and the types of accessories you need.

Complete Mattress Size Chart: Width, Length, and Depth

The following table lists every standard mattress size available in Canada, with measurements in both inches and centimetres. Note that depth varies by specific model rather than by size category, so we list the typical range you will encounter when shopping. For a comparison of sizes ordered from smallest to largest, see our bed size order guide.

For a detailed look at these sizes in feet, visit our bed sizes in feet guide. For inch-specific breakdowns, check our bed sizes in inches reference.

Specialty and Less Common Sizes

Beyond the seven standard sizes, you will occasionally see specialty mattresses. These are less common in Canadian bedrooms but worth knowing if you are shopping for an unusual frame or a non-standard space.

The split King is the one most Brantford customers ask about. Because a King and two Twin XL mattresses share the exact same 76 x 80 inch footprint, a split King lets couples on an adjustable base raise or lower each side independently. One partner can elevate their head to read while the other stays flat. If you are exploring power bases, our adjustable bed frame sizes guide walks through how split configurations work with Canadian standards.

What Size Is a Standard King Mattress?

A standard King mattress in Canada measures 76 inches wide by 80 inches long, or 193 cm by 203 cm. It is the widest standard size sold in Canada and gives each person in a couple 38 inches of personal space, the same width as a standalone Twin mattress. A King shares its 80-inch length with the Queen and Twin XL, so tall sleepers get the same legroom as a Queen but with far more shoulder-to-shoulder space.

People often confuse the King with the California King. They are not the same. A standard King is wider (76 inches versus 72) while a California King is longer (84 inches versus 80). If your priority is width for sharing the bed, the standard King wins. If your priority is length for a sleeper over 6'2", the California King wins. Very few people need both, which is why the standard King remains the most popular large size in Canadian master bedrooms. If you are sizing up to this footprint, browse the King-size mattresses we carry to see how depths from 10 to 15 inches change the feel.

Understanding the Four Depth Categories

Mattress depth (also called profile or thickness) is the measurement from the bottom of the mattress to the top of the sleep surface. Modern mattresses fall into four general depth categories, and knowing which category your mattress falls into will help you choose the right sheets, bed frame, and foundation.

Low-Profile: 8 to 10 Inches (20 to 25 cm)

Low-profile mattresses are the thinnest adult options on the market. They typically feature a simple construction with one or two comfort layers on top of a support core. You will find low-profile mattresses in basic innerspring models, some all-foam beds designed for bunk beds or trundle frames, and guest room mattresses where maximum comfort is not the primary concern.

These mattresses work well for children, lighter-weight sleepers, and situations where total bed height needs to stay low (such as a platform bed without a foundation). Standard-depth sheets fit these mattresses without any issues. However, heavier sleepers may find that an 8-inch mattress does not provide enough cushioning to prevent bottoming out, which can lead to pressure points and disrupted sleep. In a child's room or guest bedroom, our Twin-size mattresses mostly sit in this lower-profile range.

Standard: 10 to 12 Inches (25 to 30 cm)

The 10- to 12-inch range is where most mid-range mattresses sit. This depth allows manufacturers to include a proper comfort layer (usually 2 to 3 inches of foam or latex), a transitional layer, and a support core (either innerspring coils or high-density foam). The result is a mattress that balances comfort and support for the widest range of body types and sleep positions.

Standard-depth sheets (fits up to 12 inches) work with these mattresses. Most bed frames and adjustable bases are designed with this depth in mind. If you are replacing an older mattress that was in the 8- to 10-inch range, you may notice a slight increase in total bed height but nothing that requires new accessories.

Thick/Deep: 12 to 14 Inches (30 to 36 cm)

Thick mattresses in the 12- to 14-inch range represent the premium tier for many brands. The extra depth allows for additional comfort layers, specialized pressure-relief foams, and reinforced edge support systems. Many popular hybrid mattresses (which combine innerspring coils with foam comfort layers) fall into this category because the coil unit alone can be 7 to 8 inches tall.

At this depth, you will likely need deep-pocket sheets that accommodate up to 15 inches. Your existing bed frame should still work, but if you are using a box spring underneath, the total bed height may reach 22 to 24 inches, which some people find too tall for comfortable entry and exit. Consider a low-profile foundation (4 to 5 inches) instead of a standard box spring (8 to 9 inches) if height is a concern.

Flagship/Ultra-Thick: 14 to 15+ Inches (36 to 38+ cm)

The thickest mattresses on the market are reserved for flagship models that prioritize maximum comfort layering. These mattresses often feature multiple zones of individually wrapped coils, several inches of specialty foams (memory foam, gel-infused foam, latex), quilted pillow-top or Euro-top layers, and reinforced perimeter support. The Restonic Revive St Charles & Elizabeth, for example, stands a full 15 inches tall with copper-infused latex over a robust coil unit, and every inch of that build shows up in your sheet and frame requirements.

At 14 inches and above, you absolutely need deep-pocket or extra-deep-pocket sheets. Standard fitted sheets will pop off the corners during the night, which is both annoying and disruptive to sleep. You should also measure your bed frame rails to ensure the mattress does not sit above them, and confirm that the total bed height (mattress plus foundation or platform) works for your needs.

How to Measure Your Current Mattress

Before you shop for a replacement, measure your existing mattress to establish a baseline. This tells you exactly what size you have now and whether you want to go larger, smaller, or stay the same. Here is the proper technique:

Tools You Need

A rigid tape measure (the retractable metal kind) gives more accurate results than a fabric sewing tape, especially for depth measurements. If you only have a fabric tape, lay it against a rigid straightedge like a yardstick or level.

Measuring Width

Remove all bedding, including the mattress protector. Place one end of the tape measure at the left seam of the mattress and extend it straight across to the right seam. Measure at the widest point, which is typically at the centre of the mattress. Take measurements at the head, middle, and foot of the mattress. If the numbers differ by more than half an inch, your mattress may have shifted or sagged, and the centre measurement is the most reliable.

Measuring Length

Place one end of the tape at the head of the mattress (the seam at the top edge) and extend it straight down to the foot. Again, measure along the centre line for accuracy. Compare this measurement to the standard lengths in the chart above to confirm your mattress size.

Measuring Depth

This is the measurement most people get wrong. Stand the tape measure vertically against the side of the mattress, with the bottom end flush against the bottom edge. Read the measurement at the highest point of the sleep surface. If your mattress has a pillow top, include it in the measurement because that is the total depth you need to account for when buying sheets and checking frame compatibility.

Do not compress the sleep surface when measuring. Let it sit naturally. If you have a pillow-top that has softened with age, it may measure slightly less than its original specification. That is normal and expected.

How to Measure Your Room for a New Mattress

Getting the right mattress for your space is just as important as getting the right comfort level. A King mattress crammed into a small bedroom leaves no room for walking, nightstands, or dressers. Here is how to measure your room and determine the best fit.

Minimum Room Dimensions by Mattress Size

Step-by-Step Room Measurement

Step 1: Measure the room's length and width at floor level, wall to wall. Record in both feet and inches for precision.

Step 2: Note the locations and sizes of doors, windows, closet openings, heating vents, and radiators. These are areas where you cannot place furniture.

Step 3: Subtract 24 inches (2 feet) from each side where you want walking space. For a shared bed, you need walking space on both sides and at the foot. For a child's bed against a wall, you only need space on one side and at the foot.

Step 4: Account for additional furniture. A standard nightstand is 20 to 24 inches wide, and a dresser is 36 to 60 inches wide. Subtract these from the available wall space.

Step 5: Compare the remaining space to the mattress dimensions in the chart above. If your available space is smaller than the mattress, go down one size.

Sheet Depth Requirements by Mattress Thickness

One of the most common complaints after buying a new mattress is that the old sheets no longer fit. Modern mattresses are significantly thicker than those made 15 or 20 years ago, and sheet manufacturers have responded by creating multiple pocket-depth categories. Here is what you need to know:

When shopping for sheets, always check the pocket depth listed on the packaging. A sheet labelled "deep pocket" from one brand might only fit a 14-inch mattress, while another brand's deep pocket might accommodate 17 inches. The safest approach is to measure your mattress depth (as described above) and buy sheets with a pocket depth at least 1 to 2 inches larger than your measurement. This gives the elastic enough slack to grip under the mattress without popping off.

Bed Frame Compatibility and Measurements

Your mattress measurements dictate which bed frames and foundations will work. Here are the key compatibility checks:

Frame Width and Length

Standard bed frames in Canada are built to match standard mattress dimensions exactly. A Queen frame has an interior measurement of 60 x 80 inches. However, if you are using an older frame, an antique frame, or a European/IKEA frame, the interior dimensions may differ by 1 to 2 inches. Always measure the inside of the frame, rail to rail, before ordering a mattress.

Foundation Height

The foundation (box spring, bunkie board, or platform base) adds height to your total bed setup. Here are common foundation heights:

To calculate your total bed height, add your mattress depth to your foundation height. For most adults, a total bed height of 22 to 27 inches is comfortable for sitting on the edge and standing up. Taller individuals may prefer 27 to 30 inches. Shorter individuals or those with mobility issues should aim for 20 to 24 inches.

Platform Beds and Slat Spacing

If you are using a platform bed with slats instead of a box spring, check the slat spacing. Most mattress manufacturers recommend slat spacing of no more than 3 inches (7.5 cm) to prevent foam from sagging between gaps. Wider spacing requires a bunkie board or solid platform insert between the slats and the mattress.

Measuring for Delivery: Doorways, Hallways, and Stairs

A mattress that fits your bedroom perfectly is useless if it cannot get through your front door. Delivery clearance is one of the most overlooked mattress measurements, and it causes real problems, especially in older Brantford homes with narrow hallways and tight staircases.

Critical Measurements to Take Before Ordering

Front door: Measure the width and height of the door opening (not the door itself, but the clear opening when the door is fully open). Most exterior doors provide a 32- to 36-inch clear opening.

Interior doorways: Measure the bedroom door and any hallway doors the mattress must pass through. Interior doors typically offer a 28- to 32-inch clear opening.

Hallways: Measure the width at the narrowest point. Pay attention to corners where the hallway turns, as a mattress must be tilted to navigate 90-degree turns.

Stairs: Measure the width of the staircase, the ceiling height at the bottom and top of the stairs, and the clearance at any landing where the stairs turn. For L-shaped or U-shaped staircases, the landing dimensions are the most critical measurement.

Delivery Clearance Guide

When a mattress is tilted on its side for delivery, the measurement that needs to clear the doorway is the depth, not the width. A 15-inch-thick King mattress only needs about 16 inches of clearance when stood on its side. The challenge comes with hallway corners and staircase landings, where the full length of the mattress (80 inches for a King) must be manoeuvred around a turn.

Restonic ComfortCare: Coil Counts by Size

For customers considering a traditional innerspring or hybrid mattress, the coil count varies by mattress size because larger sizes need more coils to cover the increased surface area. Restonic's ComfortCare line (the Dalton firm and Albany plush) is one of the most popular options we carry at Mattress Miracle, and these are the manufacturer's stated counts for its Marvelous Middle zoned pocket coil system:

Higher coil counts within a given size generally indicate better support distribution and longer mattress lifespan. The ComfortCare line holds its density near 34 to 37 coils per square foot across every size, which means a Twin and a King provide essentially the same per-square-foot support, and the "Marvelous Middle" zoning adds reinforcement through the centre third where hips concentrate the load. This consistency matters because some budget brands quietly reduce coil density in larger sizes to save on materials, so the King you order feels less supportive than the Queen you tested on the showroom floor.

The Restonic Revive St Charles: A 15-Inch Flagship

To see how mattress measurements play out at the premium end, consider the Restonic Revive St Charles & Elizabeth. At 15 inches deep, it is the thickest mattress in our Restonic collection ($3,736 queen as of June 2026), and it sits at the depth where most accessory surprises happen.

The St Charles stacks copper-infused latex and multiple comfort layers over a tall pocketed-coil support unit. The payoff is exceptional pressure relief and motion isolation with the responsive feel that innerspring fans prefer. The catch is that 15 inches of mattress makes specific demands on everything underneath and around it:

Sheets: Deep-pocket fitted sheets rated for at least 15 inches. Standard sheets will not stay on.

Foundation: A low-profile foundation (4 to 5 inches) is recommended rather than a standard box spring to keep total bed height reasonable. On a standard 9-inch box spring, the total bed height would reach 24 inches before adding the bed frame, which puts the sleep surface over 30 inches off the ground.

Frame: The frame rails must be tall enough to contain the mattress, or use a platform base where the mattress sits directly on top rather than inside rails.

Measuring Tips for Specific Situations

Couples Upgrading from Double to Queen or King

A Double (Full) mattress is 54 inches wide, giving each partner just 27 inches of personal space. That is less than the width of a standard crib mattress. Upgrading to a Queen (60 inches) gives each person 30 inches, while a King (76 inches) provides 38 inches each. Before upgrading, measure your bedroom to confirm the larger size will fit with adequate walking space. A Queen requires at least a 10 x 10 foot room; a King needs 12 x 12 feet minimum.

Tall Sleepers

Standard mattresses are 75 inches (Twin, Double) or 80 inches (Twin XL, Queen, King) long. If you are over 6 feet tall, your feet may hang off a 75-inch mattress. Choose an 80-inch option (Twin XL, Queen, King, or California King at 84 inches). The 80-inch Twin XL mattresses are the single-sleeper way to get that extra length without a Double's width. The California King at 84 inches (213 cm) is the longest standard mattress available in Canada and is ideal for sleepers over 6'2".

RV and Non-Standard Mattresses

Recreational vehicles, boats, and antique bed frames often use non-standard mattress dimensions. RV mattresses come in sizes like RV Short Queen (60 x 75 inches), RV King (72 x 80 inches), and various custom dimensions. Always measure the sleeping platform directly rather than relying on size labels when dealing with non-standard applications. For a cottage or heavy-use setup where durability matters more than a slim profile, a rugged made-in-Canada build like the Husky Natural Life mattress holds up well, though you should still confirm it clears your platform dimensions. If you need help with back pain and are choosing a mattress for any setting, our best mattress for back pain in Canada guide covers the key considerations.

How Mattress Measurements Affect Your Sleep Quality

Beyond width, mattress depth plays a measurable role in comfort. Thicker mattresses with multiple comfort layers generally provide better pressure distribution, which can reduce the number of times you wake up to shift position. In our own Brantford showroom, the customers most likely to tell us they "tossed and turned" on their old bed are almost always the ones who were sleeping on a thin, worn mattress under 10 inches that had lost its support core.

A Word on Canadian vs. American vs. European Sizing

Canadian and American mattress sizes are identical. A Queen in Toronto is the same 60 x 80 inches as a Queen in Dallas. This means any mattress manufactured by a North American brand will fit standard Canadian bed frames, foundations, and accessories. For a side-by-side breakdown, our Canadian vs. US mattress sizes guide covers the details.

European sizes, however, are different. They use metric measurements and do not correspond directly to North American standards. An IKEA Queen, for example, may be labelled differently in some regions. If you have an IKEA bed frame, measure the interior dimensions and compare to our chart above rather than relying on the size name.

The UK also has its own sizing system. A UK King is roughly equivalent to a North American Queen, which causes frequent confusion for people moving between countries. Always go by measurements, not labels, when dealing with international sizing.

Putting It All Together: Your Measurement Checklist

Before heading to the store or ordering online, complete this measurement checklist:

1. Current mattress measurements (width, length, depth) so you know your starting point.

2. Bedroom dimensions (length, width) with locations of doors, windows, and vents marked.

3. Available mattress space after subtracting walking clearance (24 inches per side) and furniture.

4. Bed frame interior dimensions to confirm your new mattress will fit.

5. Foundation height so you can calculate total bed height with your new mattress.

6. Delivery path measurements including all doorways, hallways, corners, and stairways.

7. Sheet pocket depth needed based on your new mattress's depth specification.