(
Open parenthesis (or open bracket)
PrintableASCII 40 | Hex 0x28 | U+0028
Open parenthesis at ASCII 40 begins grouped expressions in mathematics, programming, and regular expressions. In C-family languages, parentheses after a function name invoke it, while parentheses in expressions override operator precedence. Regular expression engines treat ( as a capture group delimiter unless escaped with a backslash. Lisp and its descendants (Scheme, Clojure) use parentheses as the primary structural element, earning the nickname "lots of irritating superfluous parentheses."
ASCII Code
Decimal
40
Hexadecimal
0x28
Octal
50
Binary
0010 1000
URL Escape
%28
Unicode
Code Point
U+0028
Escape
\u0028
UTF-8 Hex
0x28
UTF-8 Binary
00101000
UTF-16
0x0028
UTF-32
0x00000028
HTML Entities
Numeric
(
Hex
(
Named
&lparen;
How to Type
Windows Alt CodeAlt + 40
HTML Entity
(
Unicode InputU+0028
Source Code Representations
C / Java
"\u0028"CSS
\0028JavaScript
"\u0028"Perl
\x{0028}Python 2
u"\u0028"Python 3
\u0028Ruby
\u{0028}Frequently Asked Questions
What is ASCII code 40?
ASCII code 40 represents the Open parenthesis (or open bracket) character. In hexadecimal it is 0x28, in binary 0010 1000, and in octal 50. It is a printable character that appears as "(" in text.
How do I type ASCII 40 on a keyboard?
On Windows, hold Alt and type 40 on the numeric keypad. On Mac, you can use the Character Viewer (Edit > Emoji & Symbols). In HTML, use the entity ( or (.