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What Is the Standard Toilet Room Size? (Explained)

Standard toilet sizes vary. So, it gets a frustrating job when you have to know about all the variations before any renovations or replacements.

But this dauntingly challenging task is not as hard as you seem it might be. Here we have answered everything you need to know from scratch!

What is the standard toilet room size?

You can always increase the size of your toilet room as per your needs and comfort. Set by the international residential code (IRC), the dimensions should be at least 30 by 60 inches. The average full toilet room size is 5 feet by 8 feet, accommodating all your bathroom essentials.

Adding more to your toilet room will enhance the beauty and comfortability, but you should make sure you do not sacrifice too much from other areas. Designing houses is tricky cause you have to consider the eventual expansion of the family.

A spacious toilet room does not harm. Ultimately it increases the resell value of your home. So, for this, there are some guidelines for building your home as you will be changing homes until you find the appropriate one.

The National Kitchen and Bath Association recommends leaving about 30 inches or 2.5 feet or 76.2 cm or 762 mm in front of your toilet.

The minimum distance is 21 inches or 1.75 feet or 53.34 cm or 533.4 mm. The length is measured from the front of the toilet to the front-facing wall.

The National Kitchen and Bath Association recommends that the room’s length becomes 51 to 60 inches or 4.25 feet to 5 feet or 129.54 cm to 152.4 cm or 1295.4 mm to 1524 mm, including the toilet.

The length is taken considering that a standard toilet from front to back is 30 inches or 2.5 feet or 76.2 cm or 762 mm.

According to National Kitchen and Bath Association’s guidelines, the recommended width for a toilet room is 36 inches or 3 feet or 91.44 cm or 914.4 mm. The minimum can be set to 30 inches or 2.5 feet or 76.2 cm or 762 mm, but no smaller than that.

Are all toilets standard size?

Not all toilets are not a standard size. Various toilet manufacturers produce toilets of different features and dimensions. The sizes vary from toilets to toilets, but it is not that frustrating. Toilets fall under some ranges that are discussed below.

The standard depth of toilets set out by ADA is around 27 to 30 inches, about 68 cm to 76.2 cm. The depth is the length of the toilet from back to front. The width measures approximately 20 inches, but toilets can have a little more or less.

Since the seat varies from toilet to toilet, the width also varies. The seat can be of rectangular, oval, circular shapes. So, the seat height also depends on the seat you are using.

The seat height should be between 17 to 19 inches, about 43 cm to 48 cm. The overall height can range from 21 inches to 30 inches.

How big should a toilet room be? How narrow can a toilet room be?

As for vastness, there are actually no specific guidelines for how big a toilet room can be. You can keep your toilet room separated from the central part of your bathroom.

You can also integrate the toilet inside your bathroom, making the toilet room even bigger. There are guidelines on the measurements regarding toilets, but you can build a toilet room as big as you want.

Before constructing a toilet room, you have to consider several factors. How often will you change your home, or how many family members will you have.

Because one common mistakes household makes is that they underestimate the numbers and build a smaller toilet room. A smaller toilet room will feel congested and will have low resale value.

While the narrowest you can make a toilet room is 50 inches in length and 30 inches in width. The recommended measurements are bigger than these. It would be best not to build below the minimum specs as it will feel utterly inconvenient.

Now the recommended measurements given by the National Kitchen and Bath Association are 60 inches in length and 36 inches in width, considering the toilet is a standard one.

You can do 72 inches by 48 inches build for additional storage capacity.

How much space do you need for a toilet? – Toilet room dimensions code

Different toilets have different dimensions, so let’s see how much space you will generally need.


The length could be 27 inches to 32 inches. Considering the standard measurements of a toilet, you will need around 30 inches of length.

For toilet rooms, that amounts to additional 30 inches of length. Before installing a toilet, make sure you have more than 60 inches to spare in your toilet room.


The width should be 20 inches. The standard toilets could vary around this value, but it is 20 inches or 51 cm on average.

To accommodate a toilet of 20 inches width, the room must have a minimum of 30 inches width. The National Kitchen and Bath Association recommends having a width of 36 inches for the room.


The depth of the standard toilets varies from 28 inches to 30 inches. So you need about 60 inches of length to fit in a toilet of the depth of 30 inches.

How to measure a toilet?

Measuring toilets can be tricky since there are lots of variants available in the market. You have to factor in toilet seat types, back height, depth of toilets.

Since there are various toilet seats available, measuring them also varies. Measuring toilets constitute a similar process. They are discussed below.

You will need a measuring tape.

Seat height:

Hold one end of your measuring tape from the ground and measure the top of your seat height. If your seat has curves, measure the topmost surface of your seat height.

Make sure the measuring tape isn’t bent due to the curve of the toilet bowl.

Back height:

The back height is the distance from the floor to the top of the toilet tank. Place one end of the tape firmly on the floor and measure the top of the tank.

In most cases, the tank should be adjacent to the wall, so it is easier for you to measure the length.


Hold the measuring tape across the toilet seat to measure the width. The width depends on the type of toilet seat you have. Toilet seats are of oval, circular and rectangular shapes.

The tank may be wider than the toilet seat, but that does not matter as the width of the toilet only means the width of the seat.


The depth of a toilet means the distance from the back to the front. You can measure from the wall, or you can measure from the end of the tank.

How many toilet sizes are there?

There are more or less about four toilet sizes that are used across states. There are standard toilets, wall-mounted, wall hung toilets. The dimension of a toilet depends on the features it provides.

A wall-hung toilet will require less space as there is no tank visible. The family number matters as well when deciding the toilet sizes.

If you have more people in your house, you are better off with a bigger toilet. Otherwise, a smaller toilet will suffice.

Back to Wall 1 Piece Toilet:

This set of toilets is suitable for small toilet rooms or bathrooms. The homes that consist of fewer members will get great utility out of it.

The Back to Wall 1 Piece Toilet has a depth of 28 inches and a width of 16 inches.

Back to Wall Long 2 Piece Toilet:

This set of toilets is suitable for medium to large toilet rooms or bathrooms. Families with more members will be served efficiently by these toilets.

The width of this toilet is 14 inches. The seat height is 17 inches. The depth is 30 to 31 inches. For its measurements, it is suitable for tall people.

Wall Hung Toilet:

To satisfy the high-end needs of toilets or complement modern bathrooms, there is no alternative to all hung toilets.

The distance of the seat from the floor is about 14 inches. The depth is about 23 inches, and the width is approximately 4 inches.

Final Thoughts

There is no standard size for toilet rooms; however, the NKBA and ADA have some guidelines regarding how narrow your toilet rooms can be. If you make the toilet room too narrow, it will feel congested. but a minimum of 30 by 60 inches can be considered as a standard size.