What Is Unicode? Code Points, UTF-8 and U+ Codes Explained Simply

Explainers · 5 min read · Published October 25, 2026

Quick answer: Unicode is the international standard that gives every character a unique number: every letter, digit, punctuation mark, symbol and emoji, in almost every writing system. That number is called a code point and is written like U+00A9. Because phones, computers and websites all use the same numbers, a © typed in Japan shows up as © in Brazil.

Quick reference: every method

Every Alt code below is verified against the real Windows code pages — where none exists we say so, rather than list one that won’t work.

The problem Unicode solved

Early computers stored each character in a single byte, which leaves room for only 256 characters. Different companies and countries filled those 256 slots differently: the same byte could mean é on one system, a Greek letter on another and a box-drawing line on a third. These tables were called code pages. Text moved between systems turned into nonsense, and no single table could hold Chinese, Arabic and English together.

Windows Alt codes come from that era. They are positions in two old code pages, which is why they stop at 255 (see what Alt codes are and how they work). Unicode replaced all those tables with one shared list that keeps growing.

Code points: one number per character

A code point is written as U+ followed by a hexadecimal number of at least four digits. A few examples:

The first 128 code points are the same as old ASCII (A is 65 in both), and the first 256 match the Latin-1 character set. Everything after that is new territory: arrows, math, currency, thousands of scripts and the emoji.

The full range runs from U+0000 to U+10FFFF, room for 1,114,112 code points, divided into 17 "planes" of 65,536 each. Almost all everyday characters sit in the first plane, the Basic Multilingual Plane (U+0000–U+FFFF). Most emoji live in a later plane, which is why their codes have five digits.

How big is Unicode?

According to the Unicode Consortium, Unicode 17.0 (released 9 September 2025) contains 159,801 encoded characters, including 4,803 that were new in that version. That is only about a seventh of the available space, so there is plenty of room left. A new version is normally released each September; check the Unicode website for the current count rather than trusting old figures. You will find claims of "over 290,000 characters" online, which is not what the Consortium reports.

Characters vs glyphs: why fonts still matter

Unicode defines what a character is, not what it looks like. The drawing comes from a font, and no font contains everything. If your font has no drawing for a code point, you see an empty box instead. The text is fine; only the drawing is missing. Our guide why symbols show as boxes explains the fixes.

Some characters are also built from more than one code point. é can be stored as the single code point U+00E9, or as a plain e followed by a "combining" acute accent (U+0301), and both look the same. Many emoji work the same way: a family or a flag is a sequence of several code points that the device draws as one picture, if it knows the combination.

UTF-8, UTF-16 and UTF-32: storing the numbers

Unicode gives each character a number. An encoding decides how that number is stored as bytes:

• UTF-8 uses 1 to 4 bytes per character. Plain English letters take one byte and are identical to ASCII, which made UTF-8 the standard choice for web pages and files. For example, é is stored as the two bytes C3 A9, and 😀 as four bytes F0 9F 98 80.
• UTF-16 uses 2 or 4 bytes. Windows and many programming languages use it internally.
• UTF-32 always uses 4 bytes. It is simple, but wasteful for storage.

When a file is read with the wrong encoding, you get garbage such as é instead of é. That is the two UTF-8 bytes of é read as two separate Windows-1252 characters.

What the codes on our symbol pages mean

Every symbol page on this site shows the same character in several "languages". Taking the copyright sign as an example:

For © the Alt code and the Unicode decimal happen to be the same (169), because Windows-1252 matches Unicode for values 160–255. They differ elsewhere: Alt+0128 gives €, but € is code point 8364, not 128. And a symbol like ★ (U+2605) has a Unicode code but no Alt code at all. That's why our pages list "Not available" for Alt codes on most symbols instead of inventing a number.

Is Unicode the same as emoji?

Emoji are part of Unicode. Each one has a code point (or a sequence of them), just like letters do. The colourful pictures come from your device's emoji font, which is why the same emoji looks different on an iPhone, an Android phone and Windows. You can browse them on our emoji page, and all other characters on the symbols page.

Sources

• Unicode Consortium: Unicode 17.0 character counts
• Unicode Consortium: Latest version of the Unicode Standard

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