#
Number sign
PrintableASCII 35 | Hex 0x23 | U+0023
Number sign (ASCII 35) goes by at least five names: hash, pound, octothorpe, sharp, and number sign. In CSS, # selects by ID (#header). In URLs, # introduces a fragment identifier pointing to an anchor within the page. Python and Bash use # for single-line comments. Twitter popularized #hashtags in 2007, which spread to virtually every social platform. In music notation, # indicates a sharp (one semitone up). C and C++ use # for preprocessor directives (#include, #define).
ASCII Code
Decimal
35
Hexadecimal
0x23
Octal
43
Binary
0010 0011
URL Escape
%23
Unicode
Code Point
U+0023
Escape
\u0023
UTF-8 Hex
0x23
UTF-8 Binary
00100011
UTF-16
0x0023
UTF-32
0x00000023
HTML Entities
Numeric
#
Hex
#
Named
#
How to Type
Windows Alt CodeAlt + 35
HTML Entity
#
Unicode InputU+0023
Source Code Representations
C / Java
"\u0023"CSS
\0023JavaScript
"\u0023"Perl
\x{0023}Python 2
u"\u0023"Python 3
\u0023Ruby
\u{0023}Frequently Asked Questions
What is ASCII code 35?
ASCII code 35 represents the Number sign character. In hexadecimal it is 0x23, in binary 0010 0011, and in octal 43. It is a printable character that appears as "#" in text.
How do I type ASCII 35 on a keyboard?
On Windows, hold Alt and type 35 on the numeric keypad. On Mac, you can use the Character Viewer (Edit > Emoji & Symbols). In HTML, use the entity # or #.