variable-width encoding (into one to four bytes) and transformation format of code points for the universal character set defined by ISO/IEC 10646 and The Unicode® Standard, compatible with ASCII
Factsheet
Standard Unicode Standard
Classification Unicode Transformation Format, extended ASCII, variable-length encoding
Extends ASCII
Standard Unicode Standard
Classification Unicode Transformation Format, extended ASCII, variable-length encoding
Extends ASCII
Wikipedia
en.wikipedia.org › wiki › UTF-8
UTF-8 - Wikipedia
3 days ago - It was designed for backward compatibility with ASCII: the first 128 characters of Unicode, which correspond one-to-one with ASCII, are encoded using a single byte with the same binary value as ASCII, so that a UTF-8-encoded file using only those characters is identical to an ASCII file.
19:56
UTF-8: The Internet's current favorite text encoding scheme - YouTube
03:19
UTF8 Encoding 🌎 SIMPLE EXPLANATION (3 minutes) - YouTube
37:42
UTF-8, Explained Simply - YouTube
01:00
What is UTF-8 character encoding and why is it needed? - YouTube
08:49
什麼是unicode 標準? - YouTube
13:20
ASCII、Unicode和UTF-8編碼詳解,一次徹底弄明白!簡...
Mother Eff
mothereff.in › utf-8
UTF-8 encoder/decoder
This tool uses utf8.js to UTF-8-encode any string you enter in the ‘decoded’ field, or to decode any UTF-8-encoded string you enter in the ‘encoded’ field.
Reddit
reddit.com › r/html5 › what is utf-8? i'm new to this.
r/html5 on Reddit: What is UTF-8? I'm new to this.
March 25, 2019 -
If I understand correctly, it's something to do with the way characters in a web page are displayed. I've looked it up, but I can't find any simple explanations. Could someone possibly dumb it down for me? Thanks.
Top answer 1 of 5
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Everything in a computer is a number. If we want to have letters in computers, we need to all agree on what number corresponds to what letter, this is called "character encoding". The simplest encoding is called ASCII. In ASCII, A is 65, B is 66, & is 38. ASCII characters are stored using only 7 bits, which means there's only 27=128 characters possible. ASCII works fine for encoding basic English/Latin characters, but there's way more than 128 characters in the world! Unicode is the name of a system that supports up to 1,112,064 characters, which includes letters from every major alphabet, and lots of other characters like math symbols, emojis and more. But now there's the question of how do we store these characters, how big does the "number have to be". UTF-32 is a character encoding that uses one 32 bit number for each character. This makes a lot of sense, but it wastes a lot of space. Why do we need a number big enough to hold 1,112,064 values, when most of the time we're only going to use the first 128 values. UTF-8 is a "variable length encoding". That means a lot of the time, each character only takes up 8 bits, but it can expand to up to 32 bits if necessary. This system can support any Unicode character without wasting space, which has made it the most popular character encoding. Now as for how this relates to webpages, when your browser gets a webpage from a server, it needs to know which encoding to use. If you don't specify anything, most browsers will default to ASCII. This is usually fine, since all characters required for html like < can be written in ASCII, and you can add special Unicode characters to your HTML by writing things like ♠. But if you want to include Unicode characters right in your code, then the file will be saved as UTF-8, and you will need to include a header or meta tag to tell your browser the right way to read your file. Hope that was helpful!
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It's a method of encoding characters. It's called UTF-8 because it uses 8-bit units. I wouldn't worry *too* much about it, though. Just know that it's the standard character encoding for web pages. It's probably unlikely you would need to use a different character encoding in a web site. For reference, here are all the characters UTF-8 is capable of encoding . There is 1,112,064 characters in the encoding, so it would take a hell of a long time to look through them all. It includes practically every character in use in every language in the world, so for the purposes of web content, it's about as good as you can get. Here is a nice simple explanation from W3C
Microsoft Learn
learn.microsoft.com › en-us › dotnet › api › system.text.utf8encoding
UTF8Encoding Class (System.Text) | Microsoft Learn
Encoding utf8 = new UTF8Encoding(true); // A Unicode string with two characters outside an 8-bit code range.
HubSpot
blog.hubspot.com › home › website › what is utf-8 encoding? a walkthrough for non-programmers
What is UTF-8 encoding? A walkthrough for non-programmers
November 20, 2025 - These systems paved the way for modern encoding, but they each had limitations. ASCII and ISO-8859-1 couldn’t represent every language. UTF-16 and UTF-32 could, but they required more storage space. UTF-8 was the perfect balance to efficiently handle common characters, but flexible enough to handle every symbol in Unicode.
W3Schools
w3schools.com › charsets › ref_html_utf8.asp
HTML UTF-8 Reference
The first 128 characters of UTF-8 have the same binary values as ASCII, making ASCII text valid UTF-8. The default character set in HTML-4 (ISO-8859-1) were limited in size and not compatible in multilingual environments. The default character encoding in HTML-5 is UTF-8.
Whatwg
encoding.spec.whatwg.org
Encoding Standard
The Encoding Standard defines encodings and their JavaScript API. The UTF-8 encoding is the most appropriate encoding for interchange of Unicode, the universal coded character set.
Medium
medium.com › @briannqc › utf-8-explained-its-not-8-bits-encoding-nor-32-bits-unicode-205362df9c80
UTF-8 Explained — It’s Not 8 Bits Encoding, Nor 32 Bits Unicode | by Brian NQC | Medium
July 18, 2023 - To understand these issues, we need to know how UTF-8 works. But first, let’s refresh our mind with the basics. I’m sure you’re familiar with ASCII, typically introduced in IT101. Being an American Standard, ASCII primarily focuses on representing characters, digits, and punctuation marks commonly used by American people. Its concise and effective encoding requires only 23 bytes to represent the sentence: “I’m a Vietnamese person.” But, what if I want to write that same sentence in my mother tongue, “Tôi là người Việt Nam”?
IBM
ibm.com › docs › en › i › 7.5.0
UTF-32
UTF-32 is an encoding of Unicode in which each character is composed of 4 bytes.
Arctosdb
handbook.arctosdb.org › documentation › encoding.html
Character Encoding
If any encoding erors are encountered, the entire dataset should be considered suspect. Consider running CSV through Google Sheets (or any equally competent converter) and explicitly saving as UTF. This step will not remove errors, but it may make them easier to discover.
Microsoft Learn
learn.microsoft.com › en-us › dotnet › api › system.text.encoding.unicode
Encoding.Unicode Property (System.Text) | Microsoft Learn
System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00 */ Imports System.Text Public Class SamplesEncoding Public Shared Sub Main() ' The characters to encode: ' Latin Small Letter Z (U+007A) ' Latin Small Letter A (U+0061) ' Combining Breve (U+0306) ' Latin Small Letter AE With Acute (U+01FD) ' Greek Small Letter Beta (U+03B2) ' a high-surrogate value (U+D8FF) ' a low-surrogate value (U+DCFF) Dim myChars() As Char = {"z"c, "a"c, ChrW(&H0306), ChrW(&H01FD), ChrW(&H03B2), ChrW(&HD8FF), ChrW(&HDCFF)} ' Get different encodings.
Utf8everywhere
utf8everywhere.org
UTF-8 Everywhere
In particular, we believe that the very popular UTF-16 encoding (often mistakenly referred to as ‘widechar’ or simply ‘Unicode’ in the Windows world) has no place in library APIs except for specialized text processing libraries, e.g. ICU. This document also recommends choosing UTF-8 for internal string representation in Windows applications, despite the fact that this standard is less popular there, both due to historical reasons and the lack of native UTF-8 support by the API.
MojoAuth
mojoauth.com › character-encoding-decoding › utf-16-encoding--elm
UTF-16 Encoding : Elm | Encoding Solutions Across Programming Languages
UTF-16 (16-bit Unicode Transformation Format) is a character encoding capable of encoding all 1,112,064 valid character code points in Unicode. It is widely used in various applications, particularly where compatibility with legacy systems is essential. UTF-16 uses one or two 16-bit code units to represent characters, making it memory efficient for languages with a significant number of common characters, such as Chinese, Japanese, and Korean.