Technology
ASCII Converter
Convert text to ASCII codes and ASCII codes back to text instantly. View decimal, hexadecimal, and binary representations with this free online converter.
ASCII Converter
Method
How this calculator works
Text → ASCII reads each character's numeric code point (charCodeAt) and lists them in decimal, with optional hexadecimal and binary rows. ASCII → Text parses space-separated decimal codes and maps each back to a character with String.fromCharCode.
FAQ
Frequently asked questions
What is ASCII?
ASCII (American Standard Code for Information Interchange) is a character encoding standard that assigns a unique number from 0 to 127 to letters, digits, punctuation, and control characters.
How do I convert text to ASCII?
Select Text → ASCII mode and type your text. The tool uses each character's code point to produce space-separated decimal values, plus optional hexadecimal and binary rows.
How do I convert ASCII codes back to text?
Select ASCII → Text mode and paste space-separated decimal codes (for example, 72 105). The converter maps each number back to its character using String.fromCharCode.
What is the difference between ASCII and Unicode?
ASCII covers 128 characters using 7 bits, while Unicode is a superset that can represent over a million characters. The first 128 Unicode code points are identical to ASCII.
Why do I get an error when decoding?
Decoding requires whole numbers separated by spaces. Non-numeric tokens, or values outside the valid character range, trigger a validation error so you can correct the input.