What Are the Standard Hot Tub Sizes?

Are Acrylic Hot Tubs Better?

What Are the Standard Hot Tub Sizes?

Standard-size hot tubs are just normal-sized ones; you can design them to be more convenient for small spaces.

They have a much larger capacity than a standard hot tub and get their height by being built with a smaller diameter. This makes it easier to fit in places with enough room to set up an average-size hot tub.

A standard-size hot tub measures 78 inches by 78 inches and is the most popular. Most people fit comfortably in a standard-size tub that is 78 inches by 78 inches or 80 inches by 80 inches.

However, consider going for something bigger if you have a bigger backyard. If your backyard is small, check out a standard-size tub.

This size is based on the average American hot tub; most are between 78 and 80 inches by 80 inches.

The best way to find out if you will be comfortable in this size is to try it out first. If you are uncomfortable in a standard-size hot tub, expect your feet to hang over the end when you sit in the water.

If you are comfortable in a standard size, then you should be able to sit in the water comfortably when it’s full. If the hot tub isn’t filled up, your feet should be able to touch the base.

Standard-size hot tubs are also designed for children’s use and will fit most children who are tall enough to sit and stand without falling over or hitting their heads.

They also have valves that allow you to adjust the water’s temperature and flow.

If you are still determining what size hot tub is right for you, go to your local hot tub store and ask to test out a standard one. Get the most comfortable size possible, and you will be glad you did.

Standard Hot tubSizes
Small78 inches by 78 inches
Medium84 inches by 84 inches
Large 94 inches by 94 inches

Hot Tub Dimensions: Sizes and Options

Hot tubs have different sizes, from small, homemade setups to large, commercial ones.

Here I will highlight the dimensions for the standard-size hot tubs from the major manufacturers, how the size affects tub usage, and how much space is needed.

It’s also important to note that hot tubs come in two main types: In-ground and above-ground. If you want a hot tub, it’s best to start by deciding whether you want one above or below ground.

 Small Hot TubsMediumLarge
Length 5’4″ – 7″6’6” – 7’9”7′ – 9″
Width5’4” – 6’8”6’4” – 7’9”7′ – 9’2″
Height29″ – 35″33″ – 38.5″36″ – 38″
Cleanout Access9” x 3.5”11” x 4.5”15.75” x 5.25”

What Hot Tub Shape Should You Choose


Square-shaped hot tubs are great for families and large groups because they offer the most seating space. The square offers much room to move around, so it’s perfect for larger parties.

These hot tubs are a bit tougher to fill up because they don’t have any corners, but the extra space makes it worth it.

What are the Standard Size Hot Tub?


Round hot tubs are great for smaller groups or individuals because they provide plenty of recline space.

The round shape offers extra space, and you don’t have to worry about taking up a lot of room in the corner when filling it up.


The rectangular-shaped hot tub offers comfort and space for the whole family. This is the most common shape, so it’s easy to find at any store, and it’s also easy to find online.

Most rectangular-shaped hot tubs are only a couple of feet longer than they are wide, so be careful when purchasing one less than 40 inches wide.


Oval-shaped hot tubs are great if you’re looking for something smaller. It provides the same comfort as a round one but is smaller. This would be the best alternative to a large hot tub if you have limited space.


The sunken tub can be a great option for smaller families or individuals. The sunken shape is a bit smaller than the oval shape, but it’s probably the most compact you can find.

Cordless Spa

The cordless Spa is one of the most uniquely shaped hot tubs available today. It’s great for anyone with limited space or needing to move it around often.

This is the best option for people who want a small hot tub but want to use it in their home.

How Do Hot Tub Sizes Affect the Cost?

You will pay more for larger hot tubs to operate, heat up, and take up more space.

The standard size for a hot tub is twenty-five to fifty feet in length. This will accommodate most families, with each person having private space.

If you are considering a hot tub purchase, get one that is the same size as your home’s exterior dimensions or house an inflatable model to ensure it fits into your home quickly.

A hot tub should also be about six and a half feet deep.

The standard-size tubs in the marketplace today are approximately eight and a half feet long by four and a half to six and a half feet wide.

This is the average size of most standard-sized hot tubs, although some models are slightly smaller or larger.

The initial price of a hot tub ranges between ninety to one hundred fifty dollars, with additional costs related to heating, chemicals, filter cartridges, filters, and other accessories needed for bathing.

The cost of operation for every gallon of hot tub water can vary between one and three dollars. Energy costs will also vary with your hot tub water heater, depending on how much water it holds.

What are the Standard Size Hot Tub?

The average price of an electric hot tub is two to two and a half cents per cubic foot, while the gas hot tub will cost you between three and five cents per cubic foot.

Four Size Categories of the Most Popular Hot Tubs

Just like the clothes you wear, hot tubs come in different sizes. Understanding the different size categories is important to finding the right hot tub.

The four main size categories are “Small,” “Medium,” “Large,” and “Extra-large.”


Small hot tubs measure 5’4″ to 7″ W x 29″ to 35″ H x 7’6″ to 8′ L. A small hot tub is best suited for a small space, like a bathtub or patio.

Despite the diminutive size, a small hot tub will still seat four adults comfortably and provide them with therapeutic benefits from water jets and bubbles.


Medium-sized hot tubs measure 7’10” W x 33″ H x 8’4″ to 10.5 L. A medium-sized hot tub is perfect for the average-sized family.

These hot tubs seat five adults and best suit a deck, patio, or backyard.


Large tubs measure 8’4″ to 10 L x 35″ to 40″ H x 10.5 L to 12 L in length. You must include the large hot tub if you have a balcony, deck, or backyard.

This size will seat six adults, and that extra space can accommodate your friends, family, or significant other.


Extra-large hot tubs measure 11’10” to 15 L x 40″ to 50″ H x 15′ L to 20′ in length. This is the logical continuation of the large hot tub, although it will usually be slightly larger than a typical “extra-large” sedan.

This hot tub comfortably seats eight adults but can be enjoyed with up to 10 people.

Hot Tub Seats Impact Size

Because of the seat’s shape, individual hot tub seats are often made with a side or front bucket. This means the seat is larger than a standard swimming pool seat, and your legs may only be able to reach some ends.

A hot tub with seven seats tends to be smaller, but it’s easier for more people to fit in. However, it’s also useful if there are more guests to entertain and lounge about.

A hot tub with more than seven seats might be difficult to fit into a smaller than 10,000 square feet home.

A hot tub with only five seats should be fine in a smaller living room, but it might become cramped in a larger space.

Number of PeopleDimensions
2183cm x 183cm x 74cm
4203cm x 203cm x 84cm
7254cm x 231cm x 97cm

How Long Does It Take to Fill Different Spas in Gallons?

On average, it takes between 1-hour and 1.5 hours to fill a 400 to 500-gallon hot tub or zero-depth pool. If your Spa has a large filter and is in a closed unit, you can expect to fill it in 2-to-2.5 hours.

With an average tub of 500 gallons, the process should take 3 hours and 12 minutes to complete.

However, some Spas may require up to 5 hours or more if they are difficult to access due to the size of the water heater or filter system within the tub.

On average, the capacity of a jacuzzi Spa takes less time to fill than a larger hot tub due to its smaller container. Because of the smaller size of a jacuzzi unit, it’s also easier to see which parts have been filled or not filled.

What are the Standard Size Hot Tub?

If you are filling your Spa from an external source, such as a water softener or an irrigation system, you can expect this process to take less time than if you were filling it from an internal source.

Due to the filter and size of the hot tub, it takes longer for a full Spa to reach 115 degrees Fahrenheit, which is the normal operating temperature.

A garden hose contains approximately 70 degrees Fahrenheit water, so for the water in your hot tub to reach the recommended temperature of 90 degrees Fahrenheit, you will need to let your Spa run for several hours.

After it has been filled, run your filter for roughly one hour before you use your hot tub or pool. This will ensure that your filter works properly and filtration will be effective.

What Is the Fastest Method to Fill A Hot Tub?

Heat the Water in Your Hot Tub with A Water Heater

Using a water heater to heat your hot tub is the fastest and most cost-effective way to fill it with hot water.

If your Spa is set up directly next to the furnace area in your home, you can use that outlet to fill the hot tub.

If it’s not, try using an outdoor faucet or hose bib for this purpose. If you own a gas water heater, you can use a gas line to fill the hot tub quickly.

Fill the hot tub directly from an outdoor hose bib

An outdoor hose bib is the easiest way to fill your hot tub. With this method, you can use a garden hose or any large, flexible plastic pipe to direct water into your bathtub.

Just make sure that you check the pressure of the water coming directly from your outdoor hose bib before doing this.

Portable Tank-Style Water Heaters

If your outdoor hose bib doesn’t provide access to an outside gas or electrical outlet, or you don’t have one or don’t want to use it for such a purpose, consider renting or buying a portable tank-style water heater.

You can fill the hot tub with hot water without using gas lines.

How Thick Should a Slab Be for A Hot Tub?

The concrete base needs to be a minimum of 4 inches thick (ideally 6 inches) for a hot tub (or any other significant weight, for that matter).

This is because all the weight will be resting on it. Some people prefer to make the base as thin as possible, which can lead to disaster!

The load on the concrete is calculated by multiplying the area of the hot tub footprint by the maximum allowed total moisture content of the concrete. This moisture content can vary depending on your location.

The maximum allowed moisture content will also get listed on your mix bag differently than above, typically as a percentage (which needs to be converted).

So, for example, if your bag is labeled “30%”, convert this to an allowable weight by using the following formula:  Allowable weight = (1440 / 30) x 465.5 = 407.5 lbs/ cubic foot.

The maximum allowable weight then has to be divided by the minimum required thickness of the concrete base. In this example, we get 3.8 feet (4 inches) result.

This means that if you have a concrete slab with a hot tub footprint of 8 feet by 8 feet, it needs to be at least 4 inches thick (8 x 4 = 32 inches, 32/3.8 = 16 inches).

If you’re using a thinner slab and only have the 8-foot by 8-foot hot tub footprint available, it will be fine with a thinner slab.

How Many Gallons Are in A Hot Tub? -How To Calculate

A Hot tub boats 7.5 gallons per cubic foot. To get the gallons volume, multiply the number of cubic feet of water in the tub by 7.5.

For example, a hot tub that holds 60 cubic feet or 12,000 gallons would result in 72,000 gallons of water. This number can vary depending on how many people use the hot tub at once and how often it’s heated.

Hot tubs or Spas are readily available amenities often used in many homes. They are not only convenient to have, but they also provide a unique experience that anyone can enjoy and benefit from.

While it can be nice to use the hot tub without thinking about anything else and enjoy the time relaxing with friends and family.

It’s important to understand how much water is on the hot tub so that you know exactly how much time you can spend in there before draining.

You want to use the hot tub for as long as possible without worrying about running out of water. Knowing the number of gallons in a hot tub is so important.


Hot tubs have been widely popular lately as home Spas. Many people purchase one to meet their needs, whether for back pain, arthritis, or just because they want to relax during their leisure time or even on weekends.


Hi! I' am Tom. I was a manager in one of the biggest stores for over 10 Years, am also an SEO by night. I don't like to call myself a blogger; they are very analytical, do email marketing, and know all SEO stuff. I faced many questions from customers about different products, and there was hardly any help on the internet. After learning all the things about these products as a manager the hard way, I decided to start a blog and help other people.

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