ASCII to Decimal Conversion Table: Complete

The complete ASCII to decimal conversion table.

This ASCII to decimal table contains all 256 ASCII characters and their decimal counterparts.

So if you want to get the complete ASCII to decimal conversion table, then this article is for you.

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ASCII to Decimal Conversion Table: Complete (PDF File)

What Is ASCII in a Nutshell?

Have you ever stopped to wonder how your computer works?

You may know that computers use binary (combinations of the numbers zero and one) to store information, but how does that translate into the comprehensive text you read on your screen?

The answer lies with ASCII.

ASCII Explained

ASCII stands for the American Standard Code for Information Interchange. Essentially, it is the computer’s own language.

Computers have a seven-digit code to represent each letter, number, and punctuation. This code is binary, so it only uses a combination of zeros and ones. 

For example, the bits (binary digits) for a capital A are 01000001, while the bits for a lowercase A are 01100001. 

If you counted how many digits there are, you might be confused about why there are eight digits instead of seven.

Well, each byte in the standard ASCII starts with zero, so the following seven digits are those that differentiate the characters.

ASCII has codes for 255 characters.

Instead of remembering the byte for each letter, symbol, and number, the founders organized them numerically and assigned them a decimal value.

For example, capital A (as mentioned above) is number 65, while the lowercase A is 97. 

ASCII Sections

To further organize these codes, the founders separated the characters into two sections, which later became three as people developed codes for more specialized characters. 

The first ASCII section is a control group that contains unprintable characters.

There are a total of 32 characters in this subgroup, labeled from 0 to 31.

These unprintable numbers are only to control different external devices, like a keyboard or a printer. 

In the next section, you’ll find the printable characters that occupy spaces 32 to 127.

Any character you see on the keyboard will be in this group, from the % symbol to the letters and numbers.

Even the spacebar and the delete key have their own codes (numbers 32 and 127, respectively). 

The final section, ranging from character code 128 to 255, was a more recent addition.

Every code has eight bits, each starting with one (as opposed to zero as in the previous two sections).

The characters in this section vary depending on the particular operating system language you are using. Many foreign characters (like Á and Ö) fall into this category.

History of ASCII

Sixty years ago, a conversation about creating a unified coding system for all types of characters began.

The first meeting of the American Standard’s Association’s subcommittee X3.2 occurred in October 1960, and the members started with a teleprinter code from the Bell company. 

From there, they published the first version in 1963, which only had numbers and capital letters. In 1967, they added the first section of control characters and lowercase letters. 

Fourteen years later, they implemented the extension group. This third section includes characters from 128 to 255. 

The majority of computing systems still use ASCII, but new variations are becoming popular with specific systems.

Using the ASCII

Whether you’ve realized it or not, you already use ASCII! Just using a computer system utilizes the ASCII. 

Focused employee using a laptop in his office.

Nevertheless, it’s helpful to learn and understand ASCII—even if you aren’t interested in the technical details – so you can quickly get a foreign language letter whenever you need it. 

For example, with Windows, you can press the ALT key and the given code to get any particular character.

Instead of copying and pasting those accented letters or unique currency signs, you can use this quick method not to break the flow of your typing. 

Variations of ASCII

Since the ASCII contains mainly American characters, several variations with non-English letters developed around the world.

The International Organization for Standardization (ISO) created the third section of the ASCII, including eight-bit codes.

The extension, called the ISO 8859, has numerous language variations.

  • Western European languages: Latin-1
  • Eastern European and non-Cyrillic central languages: Latin-2
  • Esperanto and southern European languages: Latin-3
  • Northern European languages: Originally Latin-4, now called Latin-10 or Latin-6
  • Turkish: Latin-5
  • Cyrillic: 8859-5
  • Arabic: 8859-6
  • Greek: 8859-7
  • Hebrew: 8859-8

The numerous names for the code for northern European languages show that the information interchange code is continually changing as people develop more efficient systems.

A fantastic example of these continual changes is the creation of Unicode.

The Universal Coded Character Set aims to provide a completely comprehensive code set for all characters.

There are currently 143,859 characters, including historical scripts and emojis. 

Thanks to its goal of including thousands of characters, it has become a popular choice for computer software.

Learn every little tiny bit about ASCII in this in depth article about ASCII: What Is ASCII & What Is ASCII Used For?

What Is the Decimal Numeral System in a Nutshell?

The decimal numerical system was created to separate integer and non-integer numbers.

This is the standard system used worldwide in all types of mathematical applications.

Often, decimals are denoted using a “.” or “,”. Both of these notations are commonplace.

Yes, that’s right, we’re talking about the decimals you learned in 4th-grade math.

Remember when your teacher would ask you to round to the nearest decimal place, and you would look at her confused?

Well, here’s the bottom line:

What is the Origin of the Decimal Numeral System?

This will surprise you.

The decimal numeral system dates back thousands of years to many primitive civilizations.

It is believed that these ancient civilizations used ten and its powers to denote numbers.

Stories passed down from these ancient peoples point towards the selection of the number ten due to humans possessing ten fingers. 

Of course, the term “decimal system” came about quite a bit later; in 1841 to be exact.

But for thousands of years, the decimal system, whatever name it went by, has been the go-to for humans to count.

The Influence of Ancient Civilizations

According to “The History of Arithmetic”, by Louis Karpinski, one of the most prominent ancient peoples to use the decimal system was the Indus Valley Civilization, which used weights based on mathematical formulas and other types of ratios.

These weights consisted of ratios of 1/20, 1/10, 1/5, 1/2, 1, 2, 5, 10, 20, 50, 100, 200, and 500. 

The ancient Egyptians and Cretans were also pioneers in mathematics.

For example, hieroglyphics, the famous Egyptian writings, were based on an early decimal system.

The ancient Greeks then adopted this revolutionary system, as the ancient Greeks’ numbers were denoted in powers of ten as well. 

Roman numerals were also prominent, as each numeral was denoted in powers of ten, and is still in use today in many parts of the world.   

In a sense, the fingers on two hands are the very origin of mathematics.

Patient mom teaching her child with counting.

Ancient peoples used their fingers to count, add, and subtract. It’s incredible how something so simple could form the basis of mathematics!

The decimal system’s invention led to other mathematical feats, such as addition, subtraction, multiplication, and division, which have been the core building blocks of mathematics for thousands of years. 

As the years went on and the human brain continued to develop, the decimal system and mathematics became the foundation of human society. 

What is Decimal Notation?

In a nutshell, the decimal notation is any real number or fraction that uses the base of ten, and any number between 0-9, followed by a decimal point.

Here is an example of decimal notation that you may remember from grade school, 4537000.

You would write this as 45.37 in decimal notation.

Decimal notation depicts numbers in ten decimal digits, a decimal mark, and a minus sign for negative numbers.

Decimal digits are considered any number between 0-9.

Decimals notation can be written for a positive number and is always part of a whole.

Positive decimals are always greater than zero, while negative decimals are always less than zero. 

Here are some examples of decimal notation:

  • 0.7
  • 123
  • 123.008
  • 123456.1212121
Decimal numeral system.

What Are Decimal Fractions?

Decimal fractions trace their origins to ancient Chinese civilizations during the 4th century B.C.

Decimal fractions later made their way to Europe and the Middle East as well.

Decimal fractions are also a familiar concept from grade school, as they are ultimately one of the essential building blocks of mathematics.

Decimal fractions are conversions of decimals into fractions. Simple enough, even for grade-schoolers to learn.

Here is an example of a decimal fraction: the decimal 0.5 would convert to a fraction of ½. 

So, How Do You Convert Decimals to Fractions?

Now, you might be wondering how to convert a decimal into a fraction and vice versa.

When converting decimals to fractions, the first step is to put the decimal over the whole number one. 

Example: 0.5/1 

The next step would be to multiply the top and bottom numbers by the whole number ten.

Example: 0.5 x 10/ 1×10 = 5/10

The next step is to simplify the fraction to its simplest form, if necessary. In this example, five and ten both have a common multiple of 5.

Therefore, the fraction would simplify to ½.

Example: 5/5= 1, 10/5=2, therefore, 5/10= 1/2.

Complete ASCII to Decimal Table

Complete ASCII to decimal table.

Find the complete ASCII master table in this in depth article about ASCII.

Complete ASCII to Decimal Table as PDF

More ASCII Tables

If you’re looking for any other ASCII conversion table than the complete ASCII to decimal table, then you’ll find it here.

All tables come as a PDF version as well:


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    Tech entrepreneur and founder of Tech Medic, who has become a prominent advocate for the Right to Repair movement. She has testified before the US Federal Trade Commission and been featured on CBS Sunday Morning, helping influence change within the tech industry.