There are two primary factors that determine the best letter size for your sign: distance and speed. Our Letter Sizing Calculator simplifies the math for you.

**Distance: ** Enter the viewing distance (how far away you want your sign to be readable). Our calculator will calculate the minimum readable letter size. It will also provide the recommended letter size for readability.

**Speed: ** Enter the speed limit on your street and the number of seconds you want your sign to be readable. Our calculator will calculate the minimum readable letter size. It will also provide the recommended letter size for readability.

All you do is put in the viewing distance and the calculator will automaticallly show you how big your letters should be.

Approximate Viewing Distance?

Feet

Inches

Minimum Height:

Inches

Height for Easy Readability:

Inches

Height for Maximum Impact:

How far can you read a 4" tall Letter? Or any other size letter for that matter? To find out the answer, just select the letter size from the drop down list below.

Select letter size

Feet

Maximum Viewable Distance:

Feet

Distance for Easy Readability:

Feet

Distance for Maximum Impact:

Let's suppose the speed limit on your street is 45 MPH and you want your message to be readable for 3 full second by passing motorists. How would you know the right letter height? This tool will help you with that. You can also set the street speed limit too!

SPEED

LIMIT

45

SECONDS OF

VISIBILITY

TOTAL VIEWABLE

DISTANCE

Minimum Readable Letter Size:

Recommended Size For Readability

Height For Maximum Impact

When it comes to determining the size of your lettering, there are two components to take into consideration: These components are Distance and Speed. Distance applies to how far away you want your sign to be visible. Speed pertains only to signage that will be viewed by passing motorists.

You should size out your letters before sizing out your sign. Reverse engineering your sign starts with the size of the letters. The size of the letters determines how far the sign can be view-able.

Let's suppose the speed limit on your street is 45 MPH. And you want your message to be readable for 3 full seconds by passing motorists. A car traveling at 45 MPH for 3 seconds equals a viewing distance of 198 feet. Again, the Lettering Sizing Calculator will automatically give me 2 sizes:
The minimum size the letters have to be to be readable
And
The size recommended for optimal visibility.
In this case, the minimum readable size is a 6" tall letter. And the size recommended for optimal visibility is a 20" tall letter.

The viewing distance is how far away you want your sign to be legible. It is very important not to estimate or guess so our calculator can give you to optimum information. Effective signs must be legible and a distance off by 10 feet can make a difference, especially in a moving vehicle.

According the legibility index, a person with 20/20 vision can read a 6" tall letter up to 150' away. The same size letter is considered easily readable from 60' away. The factors that can affect the legibility include the viewing angle, lighting, contrast and colors.

We recommend a minimum of 3 seconds of visibility.

Our letter sizing calculator is based off from research done at The Pennsylvania Transportation Institute, Penn State University and The United States Sign Council (USSC).

Let's say you need a new business sign and you are going to be placing this sign directly on the building. How far away do you want potential clients to be able to read your message? For this example, let's assume you need the sign to be readable at least 60' away. The Letter Sizing Calculator will automatically give me 2 sizes:
The minimum size the letters have to be to be legible.
And
The size recommended for optimal visibility.
In this case, the minimum readable size is a 3" tall letter. And the size recommended for optimal visibility is a 6" tall letter. (For added advertising impact, businesses often go even larger).

When it comes to choosing sizes, most people seem a bit lost. I can see it in their faces. They just don't know how to go about it mathematically. So they take their best guess and hope the sign will turn out okay. However, hope is not a strategy.

Here's a strategy you can use right now to properly size your new signage Think backwards, That's right! If you want to size your new signage properly, it should be "reverse engineered." Don't worry, it's easy to do, once you learn this simple secret: The secret is to size your letters first, BEFORE you size your sign. After all, people don't read signs. They read the words displayed on signs. But only if the words are easy enough to read at a glance. If the letters are too small or too difficult to read, most people just won't bother. So focus on choosing the size of your lettering, first. And then fit the sign - to the size of the letters.

Which factors determine how big the letters should be? There are two primary factors that determine what size the letters should be. Of course, there are important secondary factors to consider too. And you'll have the opportunity to learn about those in our advanced guide. But to keep things simple and on point, here are the two primary factors: Distance And speed (for signs to be viewed by passing motorists). First, you need to know the viewing distance.

The viewing distance equals how far away you want your sign to be readable. Yes, I know it may take you a few minutes to determine the distance. But guessing is outright gambling. And there's really no point in taking an unnecessary risk here. Once you know the distance, we have a new type of calculator you can use. Specifically, it's a Letter Sizing Calculator. (Another handy tool thanks to our computer wizard!)

As for the speed aspect: Let's suppose the speed limit on your street is 45 MPH. And you want your message to be readable for 3 full seconds by passing motorists. A car traveling at 45 MPH for 3 seconds equals a viewing distance of 198 feet. Again, the Lettering Sizing Calculator will automatically give me 2 sizes: The minimum size the letters have to be to be readable And The size recommended for optimal visibility. In this case, the minimum readable size is a 6" tall letter. And the size recommended for optimal visibility is a 20" tall letter.

In other words, there's no need to guess at sizes anymore! The Letter Sizing Calculator simplifies the math for you Here's an example. Let's suppose you need a new business sign. And you are going to be placing this sign directly on the building. How far away do you want potential clients to be able to read your message? for this example, let's assume you need the sign to be readable at least 60' away. The Letter Sizing Calculator will automatically give me 2 sizes: The minimum size the letters have to be to be readable And the size recommended for optimal visibility. In this case, the minimum readable size is a 3" tall letter. And the size recommended for optimal visibility is a 6" tall letter. (For added advertising impact, businesses often go even larger)