๐ค ASCII Table
128 characters
A searchable ASCII code table showing decimal, hex, octal, and control character names. Useful for checking character codes or the meaning of escape sequences while programming.
How to use
- Type a character, decimal value, hex value, or control character name into the search box.
- The table filters in real time as you type.
- Click any row to copy the corresponding character or code.
How the calculation works
ASCII (American Standard Code for Information Interchange) is a character code defined in the United States in the 1960s. It assigns letters, digits, symbols and control characters to the 128 values 0โ127, which fit in seven bits. UTF-8, the dominant encoding today, is identical to ASCII for those first 128 values. Codes 0โ31 and 127 are control characters: instructions to devices rather than printable characters. The best known are 9, TAB (\t); 10, LF, line feed (\n); and 13, CR, carriage return (\r). Line endings differ by system โ Unix-like systems use LF, Windows uses CR+LF. 32 is the space, 48โ57 are the digits 0โ9, 65โ90 uppercase AโZ and 97โ122 lowercase aโz. Upper- and lowercase letters are exactly 32 (0x20) apart, so you can switch case by flipping a single bit.
Worked example
Looking up "A" Decimal: 65 Hexadecimal: 0x41 Octal: 101 Lowercase "a" is 65 + 32 = 97 (0x61). The digit "0" is 48 (0x30), so subtracting 48 from the character "7" (55) gives the number 7 โ a common way to turn a digit character into its numeric value in code.
Things to be aware of
- This covers standard 7-bit ASCII (0โ127). "Extended ASCII" (128โ255) varies between code pages.
- For characters outside ASCII, such as Japanese, use the Unicode character lookup.
- Line endings differ between operating systems (LF, CR+LF); watch for this when exchanging files.
- Most control characters are no longer used for their original purpose, such as controlling teletype terminals.
FAQ
Can I look up control characters (e.g. \n or \t)?
Yes โ control characters like line feed (LF) and tab (TAB) are listed with their names and codes, and are searchable.
Can I copy a code by clicking it?
Yes โ click any row in the table to copy the corresponding character or code.
Can I see decimal and hex together for one character?
Yes โ each row shows decimal, hex, octal, character, and name together, so you can compare them at a glance.
Does it include extended ASCII (128-255)?
It focuses on the standard 7-bit ASCII range (0-127).
How is this used in programming?
It's handy for checking character-code comparisons, understanding escape sequences like \n and \t, or specifying character ranges in a regular expression.