Supplementary Multilingual Plane

SMP

Encoding & Standards

Unicode Plane 1 (U+10000 to U+1FFFF), where the majority of emoji code points are allocated.

The SMP is Unicode's Plane 1, containing characters that didn't fit in the original Basic Multilingual Plane. It includes emoji (U+1F000 to U+1FAFF), ancient scripts, musical notation, mathematical alphanumeric symbols, and more.

The emoji blocks in the SMP include:
- U+1F300-U+1F5FF: Miscellaneous Symbols and Pictographs
- U+1F600-U+1F64F: Emoticons
- U+1F680-U+1F6FF: Transport and Map Symbols
- U+1F900-U+1F9FF: Supplemental Symbols and Pictographs
- U+1FA00-U+1FA6F: Chess Symbols
- U+1FA70-U+1FAFF: Symbols and Pictographs Extended-A

Because SMP characters are above U+FFFF, they require 4 bytes in UTF-8 and surrogate pairs in UTF-16.

Related Terms

Plane Plane
A group of 65,536 consecutive Unicode code points. Plane 0 is the Basic Multilingual Plane (BMP); most emoji live in Plane 1 (SMP). Surrogate Pair Surrogate Pair
Two UTF-16 code units (a high surrogate U+D800-U+DBFF followed by a low surrogate U+DC00-U+DFFF) that together represent a character above U+FFFF. UTF-16 UTF-16
A variable-width Unicode encoding that uses 2 or 4 bytes per character, used internally by JavaScript, Java, and Windows.

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🔢 Unicode Lookup Unicode Lookup
Enter a codepoint like U+1F600 and get the emoji, encoding details, UTF-8/16 bytes, and HTML entities.

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