ASCII (American Standard Code for Information Interchange) is a 7-bit character encoding standard that maps 128 characters to numbers 0–127. It includes control characters (0–31), space (32), printable characters (33–126), and DEL (127). Published in 1963, it remains the foundation of modern text encoding.

What is the difference between ASCII and Unicode?

ASCII covers only 128 characters (English letters, digits, symbols). Unicode extends this to over 149,000 characters, including all world scripts, symbols, and emoji. The first 128 Unicode code points are identical to ASCII for backward compatibility.

What is a code point?

A code point is the numeric value assigned to a character in an encoding system. In ASCII, "A" is code point 65. In Unicode, the same "A" is U+0041. Code points can be expressed in decimal, hex, octal, or binary.

How do I type special characters using code points?

On Windows: hold Alt and type the decimal code on the numpad (Alt+65 = A). In HTML: use A or A. In JavaScript/JSON: use \u0041. In Python: use \u0041 or chr(65).

UTF-8 is a variable-length encoding for Unicode. ASCII characters (0–127) use 1 byte. Characters up to U+07FF use 2 bytes. Most common characters use 1–3 bytes. Emoji and rare scripts use 4 bytes. UTF-8 is the dominant encoding on the web.

Why do I see weird characters in my text?

Garbled text (mojibake) occurs when text is decoded with the wrong encoding. Common causes: UTF-8 text read as Latin-1, or vice versa. Always ensure the encoding is consistent between writer and reader.

ASCII & Unicode Lookup

Look up ASCII and Unicode code points for any character. Convert between characters, decimal, hex, octal, and binary values.

CharacterEnter a single character

Character

Decimal

Hex (U+)

U+0041

Octal

101

Binary

1000001

HTML Entity

HTML Hex

JS Escape

\u0041

Code Point (decimal)Enter a decimal code point to find the character

Character

Hex

U+0000

Planning notes, formulas, and examples

About the ASCII & Unicode Lookup

The ASCII & Unicode Lookup tool converts characters to their numeric code points and vice versa. Enter a character to see its decimal, hexadecimal, octal, and binary values, or enter a code point number to see the corresponding character.

ASCII (American Standard Code for Information Interchange) defines 128 characters: control codes (0–31), printable characters (32–126), and DEL (127). It was the foundation of text encoding since 1963. Unicode extends this to over 149,000 characters across 161 scripts, covering virtually every writing system in the world.

This calculator is essential for programmers working with character encoding, HTML entities, regular expressions, and internationalization. It supports the full Unicode Basic Multilingual Plane (BMP, U+0000 to U+FFFF) and shows all common numeric representations.

When This Page Helps

Developers frequently need code point values for debugging encoding issues, writing escape sequences, creating HTML entities, and working with regular expressions. It shows instant lookup in all common formats.

How to Use the Inputs

Enter a single character in the character input field.
Or enter a decimal code point number in the code point field.
View the character alongside its decimal, hex, octal, and binary values.
Use the hex value for CSS/HTML entities (&#x...;) and JavaScript (\u...).
Check the Unicode block name for the character category.

Formula used

Character → Code Point: codePoint = char.codePointAt(0)
Code Point → Character: char = String.fromCodePoint(codePoint)
Hex: codePoint.toString(16)
Octal: codePoint.toString(8)
Binary: codePoint.toString(2)

Example Calculation

Result: Dec: 65 / Hex: 41 / Oct: 101 / Bin: 1000001

The character "A" has ASCII/Unicode code point 65 (decimal). In hexadecimal: 0x41. In HTML: A or A. In JavaScript: "\u0041". In CSS: "\0041". All uppercase Latin letters span 65–90 (A–Z).

Tips & Best Practices

ASCII 32 is space, 48–57 are digits 0–9, 65–90 are A–Z, 97–122 are a–z.
The difference between uppercase and lowercase ASCII letters is always 32.
Common escape characters: \n = 10 (LF), \r = 13 (CR), \t = 9 (TAB).
Unicode emoji start at U+1F600; they require surrogate pairs in UTF-16.

ASCII: The Foundation

ASCII was standardized in 1963 by the American Standards Association. Its 128 characters were sufficient for English text and early computing. The first 32 characters are control codes (null, bell, backspace, tab, newline, etc.), followed by printable characters starting with space (32) through tilde (126).

Unicode: Global Text

Unicode was created in 1991 to provide a unique number for every character in every writing system. It currently defines over 149,000 characters across 161 scripts. Unicode is organized into planes; the Basic Multilingual Plane (BMP, U+0000–U+FFFF) contains most commonly used characters.

Encoding in Practice

UTF-8 dominates the web (used by 98%+ of websites). It's backward-compatible with ASCII and space-efficient for Latin text. UTF-16 is used internally by JavaScript and Java. UTF-32 uses fixed 4 bytes per character. Understanding these encodings is essential for internationalization.

Sources & Methodology

Last updated: February 8, 2026

Frequently Asked Questions

ASCII (American Standard Code for Information Interchange) is a 7-bit character encoding standard that maps 128 characters to numbers 0–127. It includes control characters (0–31), space (32), printable characters (33–126), and DEL (127). Published in 1963, it remains the foundation of modern text encoding.