Unicode Blocks Explained
How the Unicode Standard organizes characters into named ranges — and how to browse every block on Symbolwise.
Browse Unicode BlocksWhat Is a Unicode Block?
A Unicode block is a contiguous range of codepoints that the Unicode Consortium has assigned a name and a purpose. Each block covers a specific set of characters — a writing system, a symbol family, or a technical notation. For example, the Basic Latin block spans U+0000 to U+007F and contains the familiar ASCII characters: English letters, digits, and basic punctuation. The Arrows block (U+2190–U+21FF) holds directional arrow symbols, while Mathematical Operators (U+2200–U+22FF) contains symbols used in formal math notation.
Every block has a fixed start and end codepoint, and blocks never overlap. A codepoint belongs to exactly one block (or to no block at all, in rare unassigned ranges). The block name is an official label defined in the Unicode Character Database, and it does not change between Unicode versions — though new characters may be added to previously reserved positions within a block.
Understanding blocks gives you a structured way to explore Unicode. Instead of searching blindly through over 149,000 characters, you can navigate by block to find exactly the set of symbols relevant to your work.
How Blocks Are Organized by Plane
The Unicode codespace is divided into 17 planes, each containing 65,536 codepoints. Blocks are allocated within these planes, and the plane a block belongs to tells you a lot about the characters inside it.
| Plane | Range | Name | Notable Blocks |
|---|---|---|---|
| 0 | U+0000–U+FFFF | Basic Multilingual Plane (BMP) | Basic Latin, Arrows, Mathematical Operators, Currency Symbols, Greek and Coptic, CJK Unified Ideographs |
| 1 | U+10000–U+1FFFF | Supplementary Multilingual Plane (SMP) | Emoticons, Musical Symbols, Mathematical Alphanumeric Symbols, Playing Cards |
| 2 | U+20000–U+2FFFF | Supplementary Ideographic Plane (SIP) | CJK Unified Ideographs Extension B, Extension C |
| 14 | U+E0000–U+EFFFF | Supplementary Special-purpose Plane (SSP) | Tags, Variation Selectors Supplement |
| 15–16 | U+F0000–U+10FFFF | Private Use Areas | Reserved for application-specific characters |
The vast majority of commonly used symbols live in the BMP (Plane 0). Emoji and many historic scripts live in the SMP (Plane 1). If you work primarily with Latin-based languages, arrows, math symbols, or currency signs, the BMP contains everything you need. If you're looking for emoji or niche symbol sets, the SMP is where to look.
Blocks vs. Collections: Official Ranges vs. Curated Sets
Unicode blocks and Symbolwise collections both help you discover symbols, but they serve different purposes.
Blocks are defined by the Unicode Consortium. They are strict codepoint ranges with official names. A block groups characters by their position in the codespace, which usually — but not always — corresponds to a thematic grouping. For example, the Arrows block contains arrow symbols, but arrow-like characters also appear in Miscellaneous Symbols, Dingbats, and Supplemental Arrows blocks.
Collections on Symbolwise are curated groups organized by theme or use case. A "Checkmarks" collection pulls together check marks, crosses, and ballot symbols from multiple blocks. An "Arrows" collection includes arrows from every block that contains them. Collections are designed to answer the practical question: "Show me all the symbols of this type."
In short, blocks tell you where a character lives in Unicode; collections tell you what kind of character it is. Both are valuable, and you can switch between them freely on Symbolwise.
Browsing Blocks on Symbolwise
Symbolwise includes a dedicated Unicode blocks browser that lists every official block in the standard. Each entry shows the block name, its codepoint range, the plane it belongs to, and the number of indexed symbols available to browse.
Click any block to see all of its characters. From there, you can click individual symbols to open their detail page, which shows full technical information — Unicode name, codepoint, script, bidirectional class, and encoding values in every format (Plain, HTML, CSS, JavaScript, React JSX, Markdown).
You can also reach a symbol's block from its detail page. Every symbol detail page shows which block the character belongs to, with a direct link back to the block view. This makes it easy to explore neighboring characters once you've found one that interests you.
The blocks browser is especially useful when you know a codepoint range or want to survey all the characters in a particular area of Unicode — something Symbolwise's search complements by letting you find symbols by name or keyword instead.
Common Questions About Blocks
Can a character appear in more than one block? No. Each codepoint belongs to exactly one block. However, visually similar characters may exist in different blocks. For example, the Greek capital letter Sigma (U+03A3, Greek and Coptic block) and the N-Ary Summation symbol (U+2211, Mathematical Operators block) look alike but are distinct characters in separate blocks.
Do all codepoints in a block have assigned characters? Not necessarily. Blocks may contain reserved positions that the Unicode Consortium has set aside for future assignments. These positions are part of the block but do not yet represent a character.
How often do new blocks get added? The Unicode Consortium releases major updates roughly once a year. Each release may add new blocks for newly encoded scripts or symbol sets, but existing block boundaries remain unchanged.
Next Steps
Now that you understand how Unicode blocks organize characters, here are some ways to go deeper:
- Browse all Unicode blocks in the Symbolwise blocks browser.
- Read What Is Unicode? for a broader introduction to codepoints, planes, and encoding.
- Learn how to find and copy any Unicode symbol using Symbolwise's search, collections, and blocks.
- If a character is not rendering correctly, see Why Symbols Show as Boxes or Question Marks for troubleshooting tips.