U0400U04FF

The range U+0400 to U+04FF represents the Cyrillic block in the Unicode standard. This block contains the central Cyrillic script used to write many languages across Eastern Europe and northern and central Asia, including Russian, Ukrainian, Bulgarian, Serbian, Belarusian, and numerous minority languages. It includes both uppercase and lowercase letters, as well as several language-specific forms that extend beyond the core alphabet.

The 256 code points in this block cover the standard Cyrillic letters as well as additional characters required by various languages. Notable examples include Ё (U+0401) and ё (U+0451), which are used in Russian and other languages; and letters such as І (U+0406), Ї (U+0407), Є (U+0404), along with the hard sign Ъ (U+042A) and the soft sign Ь (U+042C) and their lowercase counterparts. The block also contains the widely used Cyrillic letters A–Я (U+0410–U+042F) and a–я (U+0430–U+044F). Some languages employ additional diacritic-bearing or language-specific letters that are also included in this range.

Usage and encoding details: The Cyrillic block is part of the basic Cyrillic script and forms the core for many languages that use Cyrillic orthographies. All code points in this range reside in the Basic Multilingual Plane, so in UTF-16 they are represented by a single 16-bit unit, and in UTF-8 they occupy two bytes for each code point. The block is complemented by other Cyrillic blocks (such as Cyrillic Supplement and Cyrillic Extended ranges) that encode additional letters needed by minority languages and historic scripts.