Hot Tub Sizes (Standard & Popular Dimensions Guide)

So you want a hot tub, but you’re unsure what size? If you’re working with a very tight space, grab your measuring tape first. Remember that you’ll need 12-18” of clearance around the hot tub.

If you’ve got a big backyard or patio, ask yourself how many people you anticipate inviting into the spa at one time. Then, you can narrow your search by only looking at models with at least that number of seats.

Standard Hot Tub Dimensions

Hot Tub Size: (Ranges)	Length:	Width:	Height:
Small (2 to 4 People)	5’4” to 7″	5’4” to 6’8”	29” – 35”
Medium (4 to 6 People)	6’6” to 7’9”	6’4” to 7’9”	33” to 38.5”
Large (7+ People)	7’+	7’+	36” to 40”

Unfortunately, there is no such thing as a standard hot tub size. A four-person model, for instance, might comfortably fit only two or three adults, depending on their size, shape, and need for personal space.

Not only that, the configuration of the seating, the depth of the water, and the width and breadth of the tub can all vary significantly from one model to another.

On one hand, this is great — no matter your preferences, you’re sure to find a spa that suits you. On the other hand, it makes it a bit difficult to compare or even narrow down the options.

Hot tub retailers group them into three categories — small, medium, and large.

Small (2-4 People)

Small hot tubs are those with measurements in the following range: Length: 5’4” to 7″ Width: 5’4” to 6’8” Height: 29” – 35”. They usually seat two or three people.

Small 2-person Hot Tub Dimensions

One of the smallest two-person spas available is 6’6” long, 3’7” wide, and only 2’9” high. It can accommodate two people sitting face to face, but if you’d like to stretch out, it can only be used alone.

Medium (4-6 People)

A medium spa seats between four and six people. Most hot tubs are medium-sized. The length can range from 6’6” to 7’9”. Widths are between 6’4” to 7’9”. The height of a medium hot tub can be anywhere from 33” to 38.5” H.

Average 4-Person Hot Tub Dimensions

An average, square, four-seat spa model would likely be 6’2” long, 6’2” wide, and 2’10” high. Although these models are advertised for four people, they are usually more comfortable with just two or three.

Average 5-Person Hot Tub Dimensions

One round, five-person spa model measures 6” in diameter and 2’9” in height. Another square, five-person model might measure 7”1’ in length and width, and be 3” tall.

Average 6-Person Hot Tub Dimensions

A spa with lots of jets will require extra power and machinery to run, and result in a rectangular, rather than square, design. One example 6 person model has 57 jets, is 7’8” long, 8’4” wide, and 2’10” high.

Large (7+ People)

If a spa can seat seven or more people, it is considered large. These are at least seven feet long and wide. (Source Caldera) The largest pre-fabricated model available has a length of 9’ and a width of 9’2”. Large spas generally stand 36” to 40” tall.

Average 7-Person Hot Tub Dimensions

One popular, square, seven-seat spa model has a length and width of 7’10”, and a height of 3”. It comes equipped with two lounger-style seats.

Average 8-Person Hot Tub Dimensions

A rectangular, eight-seat spa model with one lounger-style seat measures, on average, 11 feet long, eight feet wide, and three feet tall.

Tub Water Depth

Besides length, width, and height, there is a third measurement that comes into play when considering a hot tub: water depth. Typically, a spa is filled until the water is about five inches from the rim. How much of your body is underwater depends partially on the size and shape of your body but also the size and shape of the supporting structure.

Some spa seats are very low, while others are higher. Children and shorter adults may prefer a shallower seat. Taller adults tend to favor deeper-set seats.

Tub Size vs. Water Capacity

Here is a breakdown of the hot tub sizes and the amount of gallons of water they hold.

Hot Tub Size	Seating Capacity	Water Capacity (approx.)
Small	2-3 people	150 to 300 gallons
Medium	4-5 people	300 to 500 gallons
Large	6-7 people	400 to 650 gallons
Extra Large	8+ people	650 to 850+ gallons

Cost to Operate a Hot Tub

The cost to run your spa will vary on several factors, such as the temperature you set and how often it is used. However, the average cost to operate a spa will cost less than $1 per day to run.

A small spa should cost about $7 to $10 a week, and a large spa should cost about $10 to $15 per week to run.

In a survey from the site Pool And Spa, “69.5 percent of people report that, on average, only two people use their hot tub at once.” With that said, one may need to consider their individual needs when it comes to buying a hot tub to make sure they are getting the best model for their needs.

Tub Weight

An empty spa usually weighs between 500 and 1000 lbs. To ensure you have adequate structural support, your foundation should be able to withstand not only the weight of the tub but also the water and the occupants.

A small spa filled with water and people weighing about 3,000lbs. A medium-sized spa in the same condition will weigh about 4,500lbs, and a large spa can be expected to weigh in at 5,500lbs.

Tub Pad Size

Hot tubs can be placed on wooden decking if there is adequate support, but many homeowners choose to pour a concrete pad instead. The pad should be, at minimum, the same size as the spa.

If exterior stairs will be needed to enter the spa, the pad should be large enough to accommodate those as well. For more related content visit our article about a Jucuzzi vs hot tub.