What Is the Optimal Viewing Distance From a 120-Inch Screen?

Today, thanks to technology, anyone can enjoy big-screen entertainment at home at a fraction of the cost of a similarly-sized TV.

I’m guessing you’ve just purchased a 120-inch screen for your home theater. You’ve probably already gone through the hassle of setting it up along with a good-quality projector. But when it comes to the viewing distance, you aren’t sure how far the seats should be for the best experience.

In this article, we’ll take a look at how far you should sit from a 120-inch screen, how to calculate the optimal viewing distance, what you should consider when deciding the optimal viewing distance and why it is recommended to be far from the screen. 

Let’s dive in.

Optimal Viewing Distance From a 120-Inch Screen

How far should you be from a 120-inch screen?

You should sit between 160 and 226.4 inches from a 120-inch screen. That means that for a multiple-row theater, the front row should be 160 inches while the last row should be 226.4 inches from the screen for the best viewing experience.  

Calculating the optimal viewing distance from a 120-inch screen

A quick search online will yield many calculators for the viewing distance that may be overwhelming for some people.

For the best estimate, two professional bodies that have been reliable for years: SMPTE and THX. Although the results will defer, they are as close as you can get to the optimal viewing distance. Let’s discuss them in detail below.


The Society of Motion Picture and Television Engineers also known as SMPTE recommends a viewing angle of 30 degrees for the optimal experience. And their formula for determining the ideal distance to sit is to divide the diagonal, in this case, 120 inches, by 0.6, which results in 200 inches or 16.67 feet.


THX, another reputable body in the movie business, recommends an ideal viewing angle of 40 degrees and a maximum viewing angle of 36 degrees. It also says that the minimum acceptable viewing angle is 26 degrees. The table below summarizes how to obtain the viewing distance for those angles.

DesignationFormulaViewing Distance (120” screen)
Ideal THX (40 degrees)screen diagonal (inches) / 0.83144.6” or 12.1 feet
Max THX Recommended (36 degrees)screen diagonal (inches) / 0.75160” or 13.3 feet
Minimum THX Acceptable (26 degrees)screen diagonal (inches) / 0.53 226.4” or 18.9 feet

See Also: Best 4K Projectors Under $500

What to consider when deciding the optimal viewing distance

In this section, we’ll cover factors that affect the optimal viewing distance from a 120-inch screen.

Seat Arrangement

Seating arrangements vary from one home theater to another. Some may have rows of seats at different levels off the ground while others may have a couch and/or a couple of recliners at the same level off the ground.

As you would expect, for a single-row theater, the optimal viewing angle and distance will be 40 degrees and 144.6 inches respectively. On the other hand, for a multiple-row theater, the ideal viewing angle and distance will vary based on the seating position. So, you have to use the ideal range recommended by THX.

For instance, if you have 3 rows of seats in your theater, the first row should be positioned at 160 inches and the third row should be positioned at 226.4 inches from the screen. 

Room Size

The room size plays a big part in determining how your viewing experience will be. You want to make sure that the room you set up your 120-inch screen is large enough to recreate a theater experience and at the same time not overwhelm it.

Too big of a room will make the 120-inch screen seem small whereas too tiny of a room will make it look gigantic. The sweet spot is a room that’s neither too big nor too small.

See Also: Best Projector Screens for Daytime Use

Mounting Height

The mounting height of your screen is as important as the viewing distance. You want to avoid a setup where the viewers have to strain their necks to watch whatever is being projected.

The ideal height is a position that aligns with or is 15 degrees lower than the eyesight level of the audience. The former is when our necks are straightened and the latter is when our necks are in a relaxing posture.   

That applies to single-row cinemas. For multi-level cinemas, you have to take into account the viewing angles of the audience at each level to ensure everyone has a pleasant viewing experience.

Personal Preference

After all is said and done, it comes down to what you prefer. What works best for one person may not be the same for another. You have to test different angles and distances to find your own sweet spot. There’s no one-distance-fits-all.

Why you should be far from a 120-inch screen

Sitting very close to the 120-inch screen for a long time will cause eye discomfort and pain. And that is because you will be focusing on a small part of the screen and moving your eyes constantly to different sections. In addition, the pixels will become visible making your viewing experience less ideal.

Final Words

In this post, we’ve covered the standard methods of determining the optimal viewing distance from a 120-inch screen as well as factors that come into play when selecting what will work best for you.

As we’ve already mentioned, you have to experiment to find the viewing distance and angle that you’re most comfortable with.