How to match Cyrillic characters with a regular expression
If your regex flavor supports Unicode blocks ([\p{IsCyrillic}]), you can match Cyrillic characters with: [\p{IsCyrillic}] or [\p{Cyrillic}] Otherwise try using: [U+0400–U+04FF] For PHP use: [\x{0400}-\x{04FF}] Explanation: [\p{IsCyrillic}] Match a character from the Unicode block “Cyrillic” (U+0400–U+04FF) «[\p{IsCyrillic}]» Note: Unicode Characters list and Numeric HTML Entities of [U+0400–U+04FF] .