How to Read Binary Code: Numbers, Letters and a Full A–Z Chart

By Abdur RehmanNovember 1, 20263 min read🖨 Print

Quick answer: binary uses only 0 and 1. Each position is worth double the one to its right — 128, 64, 32, 16, 8, 4, 2, 1 for an 8-digit byte. Add up the values where there's a 1: 01000001 = 64 + 1 = 65, which is the letter A. Every letter, number and symbol has its own 8-bit code.

Binary looks like a wall of zeros and ones, but there's only one idea to learn: place value. Once that clicks you can turn binary into numbers, and then into letters, by hand. Or paste it into the translator below and skip the maths.

Step 1: Understand place values

In everyday decimal numbers, each place is worth ten times the one to its right: ones, tens, hundreds. Binary works the same way, but each place is worth two times the one to its right.

Step 2: Convert binary to a number

Write the place values above the digits, then add up the values wherever there's a 1. Ignore the 0s.

• 1010 = 8 + 2 = 10
• 1111 = 8 + 4 + 2 + 1 = 15
• 00101101 = 32 + 8 + 4 + 1 = 45
• 11111111 = 128 + 64 + 32 + 16 + 8 + 4 + 2 + 1 = 255, the biggest number one byte can hold

To go the other way (decimal to binary), keep subtracting the largest place value that fits. For 45: 32 fits (13 left), 16 doesn't, 8 fits (5 left), 4 fits (1 left), 2 doesn't, 1 fits. That gives 101101, or 00101101 as a full byte. The number base converter does binary, octal, decimal and hex conversions instantly.

Step 3: Convert binary to letters

Computers store text as numbers using a code table called ASCII (and its modern superset, UTF-8). Capital A is 65, B is 66, and so on; lowercase a is 97. So to read a letter, convert the byte to a number and look it up.

Example: 01001000 01101001

• 01001000 = 64 + 8 = 72 = H
• 01101001 = 64 + 32 + 8 + 1 = 105 = i

It says "Hi". A space between words is 00100000 (32).

Binary alphabet chart (A–Z)

Notice the pattern: uppercase letters start with 010 and lowercase with 011. The last five digits are the letter's position in the alphabet — A is 00001 (1), Z is 11010 (26). That's the shortcut people use to read binary messages quickly.

Digits have their own codes too: the character "0" is 00110000 (48), "1" is 00110001, up to "9" at 00111001.

How to translate text to binary

1. Type or paste your text into the binary translator.
2. Click Text → Binary. Each character becomes an 8-bit group, separated by spaces.
3. To decode, paste the 0s and 1s and click Binary → Text. Spaces between bytes are optional — a continuous string of 0s and 1s is split into groups of eight automatically.

The translator uses UTF-8, so emoji and accented letters work too — they just take two to four bytes each instead of one. It can also convert text to hexadecimal, which is the shorter way programmers usually write bytes.

Where you'll actually meet binary

• Puzzles, escape rooms and geocaches often hide messages in binary — the A–Z chart above is all you need.
• Networking: IP addresses and subnet masks are binary underneath. 255.255.255.0 is 24 ones followed by 8 zeros, which is why it's written /24.
• File permissions: Unix permissions like 755 are three groups of three bits (read, write, execute).
• Binary clocks and watches show each digit of the time as a column of lights with values 8, 4, 2, 1 — add up the lit ones.

If you like codes, try the Morse code translator too — it turns text into dots and dashes and can play them as sound.

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Written by Abdur Rehman

ERP developer and AI & automation engineer who builds and maintains every tool on WebToolNest. More about me.