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ASCII to Octal Converter
Convert ASCII text to octal values in your browser with explicit ASCII, Unicode code point, and UTF-8 byte handling.
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Convert ASCII text to octal values
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Detailed conversion guide
How to Convert ASCII to Octal
ASCII assigns each character a number from 0 through 127. Converting that number from base 10 to base 8 produces its octal form. This page pads each result to three digits, so uppercase A becomes 101 and a space becomes 040.
Strict ASCII mode marks any character beyond U+007F instead of inventing an encoding. UTF-8 mode first encodes the text into bytes and then writes every byte as a three-digit octal value.
| Input | Output | Meaning |
|---|---|---|
A | 65 | 101 |
a | 97 | 141 |
0 | 48 | 060 |
space | 32 | 040 |
ASCII to Octal in JavaScript and Python
JavaScript can read a character value and call toString(8); Python can use ord and format(value, '03o'). Both implementations must reject values above 127 when the promised output is standard ASCII.
// validate first, then convert
const value = Number.parseInt(token, radix);
if (!Number.isInteger(value)) throw new Error("Invalid input");Three-Digit Octal and UTF-8 Bytes
Standard ASCII occupies octal 000 through 177. Values 200 through 377 are byte values but are not standard ASCII characters.
A non-ASCII character may require several UTF-8 bytes. For example, é becomes octal 303 251 in UTF-8 mode rather than a single ASCII value.
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