Standard Bathtub Sizes: How to Choose the Best Size for Your Bathroom

Your bathroom is most likely the smallest room in your home, so choosing a bathtub that fits your floor plan and lifestyle can be a challenge. Knowing the standard bathtub sizes can help you confidently choose the right tub for your space when hiring a pro to replace your tub. Here’s everything you need to know about different bathtub dimensions. 

Standard Bathtub Sizes by Type

Most bathtubs come in standard sizes designed to fit modern homes. Choosing the right one for your bathroom can depend on your floor plan and the type of tub you want. Here’s a handy guide to bathtub types and sizes to get you started.

1. Alcove Bathtub

Alcove bathtubs are the standard in most homes. Its name comes from the position of the tub, which is bound by three walls with a fourth wall finished with a front panel called an apron. In many cases, the alcove tub runs the length of the bathroom wall, which is typically 60 inches. 

In bathrooms with a wall longer than 60 inches, most homeowners add a wall partisan that maintains the alcove style. Aside from space, one of the main reasons the alcove bathtubs are the standard is due to bathroom safety. 

The space in front of the tub should be at least 60 inches long by 30 inches wide. These dimensions allow safe entry and exit from the tub.

While those dimensions are common, you can purchase a smaller or larger alcove tub, depending on the space. The dimensions of small alcove tubs are 54 inches in length, 30 inches in width, and 15 inches in height. Longer alcove tubs are 72 inches in length, 36 inches in width, and 20 inches in height.

2. Soaking Tub

These freestanding, oval tubs allow you to submerge yourself fully in the water. Because the plumbing for a soaking tub attaches to the exterior of the tub rather than being run through the wall, you must ensure you have enough space around the tub for the pipes.

Soaking tubs are always at least 20 inches deep, and more commonly reach 24 inches in depth. Standard soaking tubs are 60 to 72 inches long by 30 to 40 inches wide. Small soaking tubs will measure around 48 inches long and 28 inches wide. Specialty soaking tubs, like Japanese soaking tubs, can be even smaller, measuring as little as 40 inches long.

3. Drop-In Bathtub

Drop-in tubs are a popular bathtub style that shares a few similarities with the standard alcove tub. Drop-in tubs fit into an alcove in the bathroom, but instead of the tub measuring the length of the wall, it sits inside a constructed deck. Most drop-in tubs have exposed sides finished off with tile, which you can install yourself or hire a tile contractor to tackle the job.

The deck for a drop-in tub must leave at least 6 inches of flat deck space around each side of the tub, which means the deck structure must be at least 1 foot longer and wider than the tub. Drop-in tubs vary in measurement. The standard ranges are 45 to 72 inches in length, 30 to 32 inches in width, and 14 to 20 inches in height.

4. Corner Bathtub

Corner bathtubs are a luxurious drop-in tub option that’s the perfect addition to any ensuite bathroom. While it’s logical to think of the corner bathtub as fitting a space triangularly, you’ll instead want to think of it as a square shape to account for space for the entry and exit point and a deck.

Corner bathtubs work best in larger bathrooms. These tubs' dimensions are 60 inches in length, 60 inches in width, and 22 inches in height.

5. Freestanding Bathtub

Freestanding tubs, like the illustrious clawfoot bathtub, make a great focal point in your bathroom. All sides of a freestanding tub are accessible, so when you’re measuring the space, it’s best to have an extra 3 to 4 inches of space around the tub’s perimeter. 

In addition to clawfoot designs, freestanding tubs can feature pedestal or flat bottom designs. When choosing your tub design, ensure you’re taking the space into account to determine if you’ll need extra clearance. Freestanding tubs come in various sizes, but the standard sizes range from 55 to 72 inches in length, 27 to 32 inches in width, and 15 to 20 inches in height.

6. Oval Bathtub

Oval bathtubs are versatile and can be either drop-in or freestanding style. While oval tubs can appear to be larger than standard tubs, they’re only wider, measuring 60 inches in length and up to 41 inches in width. Since oval tubs are wider, they can be more difficult to fit into small bathrooms and may not even be an option if your bathroom is medium-sized.

7. Whirlpool Bathtub

If you’re looking to upgrade your bathtub to spa-level comfort, whirlpool tubs are an excellent option. While these tubs can appear larger, the size of the tub is the same as a standard alcove tub. Some whirlpool tubs can function as drop-ins as well.

The reason whirlpool tubs look a bit wider is because of the mechanism that allows the tub to operate. A thin acrylic shell goes behind or beside the tub to hide the tubes for the jet and pump. These mechanisms will add size to the space, so be sure to account for this extra area. Standard whirlpool tubs measure 60 inches in length, 32 to 36 inches in width, and 18 to 23 1/4 inches in height.

How to Measure for the Right Size Bathtub

To ensure the bathtub you buy is the right size for your space, make sure to measure correctly before heading to the store. Here’s how:

• Measure the length and width of the space you have available for the tub.

• Measure the height of the space from the floor to the top of the tub. 

• Note how deep you want the tub to be, factoring in the height of those who will use it and account for obstructions like ledges or windows. 

• Measure the space around the tub to make sure you have enough room to comfortably enter and exit.

What to Consider When Choosing a Bathtub for Your Space

Choosing the best bathroom for your space requires some planning, forethought, and an understanding of the space constraints. Because bathrooms are normally—though not always—the smallest rooms in the house, taking certain factors into consideration can help you complete the project successfully. Tips to choose a bathtub include the following. 

Location 

The type of bathtub you choose will largely depend on its location. If you want the bathtub to be set away from the wall or toward the center of the room, you’ll need to look into freestanding options. If your bathroom remodel ideas include placing the bathtub in the standard-sized alcove, you can choose from an alcove, drop-in, or oval tub, though it’s still important to measure the space to ensure the bathtub will fit. If the bathroom is larger, you can consider a corner tub or jetted tub that will take up some extra space. 

Plumbing 

The existing plumbing can help guide your decision. If you’re replacing your old bathtub with a similar one, you may just need to confirm that the plumbing will line up. For instance, plumbing for alcove or drop-in style bathtubs is in the adjacent wall—so if you’re replacing your old alcove tub for a new one, you may be able to use your existing hookups.

If you’re replacing an alcove bathtub with a freestanding model, you might have to hire a plumber to modify the plumbing. Consider the location of your drain and ask your plumber whether they’ll have to move it for the new tub. 

Code Requirements

Understanding code requirements is essential for the project to go smoothly and avoid any issues down the road. Plumbing codes vary depending on your city and state, so contacting your local municipality and working with a local bathtub installer can help you meet code requirements. You may also need certain permits before starting a bathroom remodel, so be sure to ask your contractor if permit costs are included in your bathroom remodel cost. 

Material 

Bathtubs come in various materials, including acrylic, cast iron, wood, copper, concrete, and natural stone. The bathtub material greatly impacts the price, so factor it into your budget for bathtub replacement costs. 

Acrylic

Acrylic bathtubs with fiberglass reinforcement are very light and fairly easy to install, especially if there is already existing plumbing. They work well as drop-in or alcove tubs, though they can also be used for corner tubs or whirlpool tubs. 

Copper

Copper bathtubs have superior heat retaining properties and feature the signature copper color that patinas over time. Because they’re metal, copper tubs are heavy and can be more expensive than tubs made from other materials.

Cast Iron

Cast iron is also popular for its heat retention, but like copper, it is heavy and may require extra structural support in the floor to hold its weight. The inside of cast iron tubs is coated with enamel, making it very durable. 

Wood

Wooden freestanding tubs are the ultimate in bathroom luxury and design. This material also makes a great soaking tub. When crafted right, wood bathtubs are waterproof and highly durable but often come with a hefty price tag. 

Concrete

Concrete is another material that makes excellent freestanding tubs, especially if you’re going for a clean, industrial look. Concrete bathtubs are known for their durability, but like other heavy materials, they may require additional floor support to hold their weight.

Natural Stone

Another luxury bathtub option is natural stone. These tubs are carved from one large block of stone and polished until they have a smooth surface. They come from stones like marble, granite, and travertine, among others. These tubs are extremely durable and create a stunning bathroom focal point and functional element.

How Much Does It Cost to Install or Replace a Bathtub? 

The cost to replace a bathtub falls between $2,000 and $9,400. The cost ranges widely because of the number of different factors that play into the final price. The size, shape, and brand of the bathtub is a good starting point when determining how much to budget for this project. From there, you can consider these additional factors:

• Old tub removal and disposal: $150–$4,500

• Subfloor preparation or repairs: $300–$10,000

• Faucets and finishes: $50–$900

• Permits (if necessary): $10–$500

• Labor costs: $100–$2,000

• Plumbing modifications: $400–$1,900