ASCII to Text Converter

What is ASCII?

ASCII (American Standard Code for Information Interchange) is a character-encoding standard that assigns a numeric code to each letter, digit, punctuation mark, and control character. Standard ASCII covers 128 code points (0–127): codes 0–31 are non-printing control characters (like tab and newline), 32–126 are printable characters (letters, digits, punctuation, space), and 127 is the delete character. This tool also supports extended ASCII (0–255), which adds accented Latin characters like 'é' and 'ñ' in the upper half of the range.

Each ASCII code point can be written in different number bases. This tool converts between text and two of the most common: decimal (base 10, the everyday number system) and octal (base 8, using only digits 0–7).

ASCII decimal vs octal representation

The underlying code point is identical — only the base used to write the number changes:

Character:  H    e    l    l    o
Decimal:    72   101  108  108  111
Octal:      110  145  154  154  157
Binary:     01001000 01100101 01101100 01101100 01101111

Decimal is the most widely used format today — it's what you'll see in most programming references, HTML character entities (H), and general documentation. Octal was more common in early computing on systems built around 3-bit or 9-bit word boundaries (each octal digit maps cleanly onto 3 bits), and still appears in Unix file permissions (chmod 755) and some legacy protocols.

How to convert text to ASCII codes in JavaScript, Python, and PHP

JavaScript

// Text → ASCII decimal codes
function textToDecimal(text) {
  return Array.from(text)
    .map(ch => ch.codePointAt(0))
    .join(' ');
}

// Text → ASCII octal codes
function textToOctal(text) {
  return Array.from(text)
    .map(ch => ch.codePointAt(0).toString(8))
    .join(' ');
}

// ASCII decimal codes → text
function decimalToText(codes) {
  return codes.trim().split(/[\s,;]+/)
    .map(n => String.fromCodePoint(parseInt(n, 10)))
    .join('');
}

// ASCII octal codes → text
function octalToText(codes) {
  return codes.trim().split(/[\s,;]+/)
    .map(n => String.fromCodePoint(parseInt(n, 8)))
    .join('');
}

textToDecimal('Hello');          // "72 101 108 108 111"
decimalToText('72 101 108 108 111'); // "Hello"

Python

# Text -> ASCII decimal codes
decimal_codes = ' '.join(str(ord(c)) for c in 'Hello')   # '72 101 108 108 111'

# Text -> ASCII octal codes
octal_codes = ' '.join(oct(ord(c))[2:] for c in 'Hello') # '110 145 154 154 157'

# ASCII decimal codes -> text
text = ''.join(chr(int(n)) for n in '72 101 108 108 111'.split())  # 'Hello'

# ASCII octal codes -> text
text2 = ''.join(chr(int(n, 8)) for n in '110 145 154 154 157'.split())  # 'Hello'

PHP

// Text -> ASCII decimal codes
$codes = implode(' ', array_map('ord', str_split('Hello')));  // "72 101 108 108 111"

// ASCII decimal codes -> text
$text = implode('', array_map('chr', explode(' ', '72 101 108 108 111')));  // "Hello"

// ASCII octal codes -> text
$text2 = implode('', array_map(fn($n) => chr(octdec($n)), explode(' ', '110 145 154 154 157')));  // "Hello"

Need binary instead? Our binary decoder converts binary strings to text. Working with hex bytes? See the hex decoder or hex to decimal converter. For non-ASCII multi-byte text, try the UTF-8 decoder.

Common uses of ASCII code conversion

• Learning binary/decimal/octal/hex number systems — ASCII tables are a common teaching tool for how the same value looks in different bases.
• Debugging serial/network protocols — many legacy protocols and embedded systems log raw byte values as decimal or octal codes rather than characters.
• Puzzle and CTF challenges — ASCII-code ciphers are a classic beginner-level encoding puzzle.
• Unix file permissions — while not text encoding, octal notation (e.g. chmod 644) is one of the more common places octal numbers still appear day to day.
• Data recovery from raw dumps — memory or file dumps sometimes render bytes as decimal or octal codes that need converting back to readable text.