ASCII Table
Complete ASCII character encoding reference with decimal, hexadecimal, octal, binary codes, HTML entities, and character descriptions. Search and filter instantly.
What is ASCII?
ASCII (American Standard Code for Information Interchange) is a character encoding standard developed in the 1960s that assigns numeric codes from 0 to 127 to represent text in computers and other devices. It includes 128 characters: 32 control characters (0-31 and 127) and 96 printable characters (32-126) including letters, digits, punctuation, and symbols.
What are the different number systems used in ASCII?
ASCII codes can be represented in four number systems: Decimal (base-10, 0-127), Hexadecimal (base-16, 00-7F), Octal (base-8, 000-177), and Binary (base-2, 00000000-01111111). Each system is useful in different contexts: decimal for human readability, hex for programming, binary for understanding bit patterns, and octal for legacy systems.
What are ASCII control characters?
Control characters (codes 0-31 and 127) are non-printable characters that control how text is displayed or transmitted. Examples include: NUL (0) for null termination, LF/Line Feed (10) for new lines in Unix/Linux, CR/Carriage Return (13) for new lines in older Mac systems, Tab (9) for horizontal spacing, and ESC (27) for escape sequences.
What is the difference between ASCII and Unicode?
ASCII uses 7 bits to encode 128 characters, primarily for English text. Unicode uses up to 21 bits to encode over 140,000 characters from all writing systems worldwide. ASCII is a subset of Unicode - the first 128 Unicode code points match ASCII exactly. UTF-8, the most common Unicode encoding, is backward compatible with ASCII.
What are HTML entities and how do they relate to ASCII?
HTML entities are special codes used in HTML to display characters that have special meaning in markup or are not available on standard keyboards. Numeric entities use the format &#number; where the number is the ASCII decimal code. For example, A displays as "A", < displays as "<", and & displays as "&".
Why are some ASCII characters called "control characters"?
Control characters were designed in the era of teletypes and early terminals to control device behavior rather than display visible text. For example, BEL (7) would ring a bell, BS (8) would move the cursor back, LF (10) would advance to the next line, and CR (13) would return the cursor to the beginning of the line. Many are still used in modern protocols.
What is the ASCII code for common characters?
Common ASCII codes include: Space (32), digits 0-9 (48-57), uppercase letters A-Z (65-90), lowercase letters a-z (97-122). Punctuation marks have specific codes: period (46), comma (44), question mark (63), exclamation mark (33), at sign (64), and hash/pound (35).
How do I use this ASCII table effectively?
You can search for characters by entering their code (decimal, hex, or binary) or the character itself. Use the filter tabs to view only control characters, printable characters, or all characters. Toggle between decimal, hexadecimal, and octal views to see codes in your preferred format. Click any character to copy it to your clipboard.
What is Extended ASCII?
Extended ASCII refers to 8-bit character encodings that use codes 128-255 to represent additional characters like accented letters, currency symbols, and box-drawing characters. However, there is no single "Extended ASCII" standard - different systems (ISO-8859-1, Windows-1252, etc.) define different characters for the same codes.
Why is ASCII still relevant today?
ASCII remains fundamental to computing despite newer encodings. It is the basis for UTF-8 (the dominant web encoding), used in programming syntax, configuration files, and network protocols. Understanding ASCII is essential for debugging, working with low-level systems, and understanding how text is represented in computers.
How do line endings differ between operating systems?
Different operating systems use different ASCII control characters for line endings: Unix/Linux/macOS use LF (Line Feed, code 10), Windows uses CR+LF (Carriage Return + Line Feed, codes 13+10), and classic Mac OS used only CR (Carriage Return, code 13). This can cause compatibility issues when transferring text files between systems.
What is the purpose of the NUL character (code 0)?
The NUL character (code 0) represents the absence of data and is used as a string terminator in C and many programming languages. It signals the end of a text string in memory. NUL bytes are also used in file formats to pad data to specific alignments and in network protocols for various control purposes.
Can I copy characters from this table?
Yes, you can click on any printable character in the table to copy it directly to your clipboard. This is useful for inserting special characters into your text, code, or documents. You can also copy the entire table or filtered results using the copy button.
What is the difference between printable and non-printable characters?
Printable characters (codes 32-126) are visible when displayed, including letters, numbers, punctuation, and symbols. Non-printable characters (codes 0-31 and 127) are control characters that perform actions like moving the cursor, controlling devices, or signaling the end of data. They don't display as visible glyphs but affect how text is processed.