ASCII Table Reference

ASCII (American Standard Code for Information Interchange) is a character encoding standard established in 1963 that assigns numeric values to 128 characters, including control characters, printable characters, and symbols. This reference tool displays the complete ASCII table with each character's code in four number systems: decimal (base 10), hexadecimal (base 16), octal (base 8), and binary (base 2).



The ASCII standard divides its 128 characters into two groups. Characters 0-31 and 127 are control characters — non-printable codes originally designed to control hardware devices like teleprinters and tape readers. Examples include NULL (0), TAB (9), LINE FEED (10), CARRIAGE RETURN (13), and ESCAPE (27). Characters 32-126 are printable characters, starting with SPACE (32) and including uppercase letters (65-90), lowercase letters (97-122), digits (48-57), and punctuation symbols.



This tool renders the table dynamically in your browser, allowing you to search, filter, and copy specific character codes. The interactive display makes it easy to find character values for programming tasks like bitwise operations, string encoding, serial communication protocols, or low-level data manipulation. Each entry shows the character glyph alongside its numeric representation in all four bases, with descriptions for non-printable control characters.

1. Programming & Software Development
Developers regularly need ASCII values when working with character manipulation, string comparison algorithms, encryption implementations, or communication protocols. Looking up whether 'A' is 65 or the hex value of a newline character is a common daily task during low-level programming, especially in C, C++, and assembly language.



2. Networking & Data Communication
Network engineers and protocol analysts use ASCII codes to decode raw data in packet captures, serial port communications, and protocol debugging. Understanding ASCII control characters like STX (Start of Text), ETX (End of Text), and ACK (Acknowledge) is essential for working with legacy protocols and industrial equipment.



3. Embedded Systems & Hardware
Embedded developers working with microcontrollers, UART serial communication, and display modules need ASCII codes to send text data over hardware interfaces. Converting between character representations and their numeric codes is fundamental when programming firmware that handles text input/output.



4. Education & Computer Science Courses
Students learning about character encoding, number systems, and data representation use ASCII tables extensively. Understanding the relationship between characters and their binary representations is foundational knowledge for computer science, and an interactive reference accelerates learning.



5. Data Forensics & Security Analysis
Security analysts and forensic investigators examining binary files, memory dumps, and encoded payloads use ASCII tables to identify readable text within raw data. Recognizing ASCII patterns helps decode obfuscated strings, analyze malware communication channels, and reconstruct data from disk images.

• Memorize key anchor points: Remember a few critical ASCII values and derive others: 'A' = 65, 'a' = 97, '0' = 48, SPACE = 32. The difference between uppercase and lowercase is always 32 (one bit flip), which is useful for case conversion in low-level code.



• Use hex for memory and binary analysis: Hexadecimal is the preferred representation when reading memory dumps or binary files because each hex digit maps exactly to four binary digits (one nibble), making mental conversion straightforward.



• Understand control character origins: Many control characters were designed for teletype machines and have evolved meanings in modern computing. CR (13) and LF (10) still define line endings — Windows uses CR+LF, Unix uses LF alone, and classic Mac OS used CR alone.



• Recognize printable range quickly: Characters 32-126 are printable. Anything outside this range in a text stream is either a control character or potentially indicates binary data or a different encoding like UTF-8 multi-byte sequences.



• Use ASCII for simple encryption exercises: Shifting ASCII values by a fixed number (Caesar cipher) or XOR-ing with a key are classic exercises that teach fundamental cryptographic concepts. The ASCII table makes these transformations visual and understandable.



• Know the digit-to-value conversion: To convert an ASCII digit character to its numeric value, subtract 48 (or 0x30). This is faster than calling parsing functions in performance-critical code and is a common pattern in C and assembly programming.