ASCII to Binary Converter

What is ASCII to Binary Conversion?

ASCII (American Standard Code for Information Interchange) is a character encoding standard that assigns a unique number (0–127) to each letter, digit, punctuation mark, and control character used in English text.

Since computers only understand binary (sequences of 0s and 1s), ASCII values are stored as 8-bit binary numbers — one byte per character. For example:

• The letter 'A' has ASCII value 65, which in binary is 01000001
• The letter 'a' has ASCII value 97, which in binary is 01100001
• The digit '0' has ASCII value 48, which in binary is 00110000
• The space character has ASCII value 32, which in binary is 00100000

ASCII was developed in the 1960s and remains foundational to modern computing, forming the basis for Unicode (which extends it to cover over 100,000 characters).

How Does ASCII to Binary Conversion Work?

Converting ASCII text to binary is a two-step process:

1. Step 1 — Look up the ASCII value: Each character has a defined decimal value in the ASCII table. For example, the letter 'H' = 72.
2. Step 2 — Convert the decimal value to 8-bit binary: Divide the number by 2 repeatedly and record the remainders: 72 → 1001000 → padded to 8 bits → 01001000.

That's it. For multi-character text, the tool converts each character individually and separates the results with spaces. To reverse (Binary → ASCII): take each 8-bit group, convert it to decimal, then look up the corresponding character in the ASCII table.

Convert "Hi" to Binary (Worked Example)

H ASCII = 72 Binary = 01001000 i ASCII = 105 Binary = 01101001 Result: 01001000 01101001

ASCII to Binary Conversion Examples

ASCII Character to Binary Table (Quick Reference)

How Many Bits Does ASCII Use?

Standard ASCII is a 7-bit character encoding with 128 values from 0 to 127. However, ASCII characters are commonly represented inside 8-bit bytes, so a standard ASCII value is often shown with a leading zero when displayed as an 8-bit binary value.

For example:

• A = 65
• 7-bit binary = 1000001
• 8-bit byte representation = 01000001

Does ASCII Support Unicode Characters?

Standard ASCII only defines 128 characters with values from 0 to 127. Characters such as é, ₹, 中, and emojis are outside standard ASCII and require a larger character encoding such as Unicode/UTF-8.

If your input contains non-ASCII characters, use a UTF-8 or Unicode-aware text-to-binary converter instead of treating those characters as standard ASCII.

Binary to ASCII (Reverse Conversion)

Need to decode binary back into readable text? Our tool supports bidirectional conversion. Simply paste your space-separated 8-bit binary values into the output field and click the "Binary to ASCII" button. You can also use our dedicated Binary to ASCII Converter.

100% Client-Side Privacy

Your text stays in your browser. This converter processes ASCII-to-binary conversions locally and does not need to upload your input to our server.