Latin to Cyrillic Converter

Purpose & User Intent: This tool provides a deterministic transliteration from Latin-script text to Cyrillic, intended for editors, translators, language learners, content teams, and researchers who need consistent script conversion without translation. It is useful when preparing multilingual materials, indexing content in Cyrillic scripts, or performing linguistic data tasks where the Latin input must be rendered in Cyrillic for study or display.\n\nCore Logic & Features: The engine uses a rules-based mapping with per-letter transliteration and common digraphs (kh, ch, sh, ts, ya, yo, yu). Required features include case-preserving mapping, punctuation and digit passthrough, and batch processing. Optional features include language presets for Russian, Ukrainian, and Bulgarian, custom mapping tweaks, and an API-friendly batch workflow.\n\nInputs & Outputs: Input is Latin-script text; output is Cyrillic-script text. Inputs: text string, optional preset parameter selecting 'Russian' (default), 'Ukrainian', or 'Bulgarian'. Sample: "Privet" -> "Привет". Validation: non-empty UTF-8 string; invalid characters preserved or mapped by preset. Outputs: transliterated_text string; digits and punctuation preserved; line breaks retained.\n\nAlgorithms & Calculations: The core applies a digraph-first approach followed by per-letter substitutions using a canonical mapping table. It preserves case by mapping source-case to target-case; diacritics are mapped to closest Cyrillic equivalents or removed; non-Latin characters are kept as-is. Batch processing splits input into chunks for performance and concatenates results.\n\nError & Edge Cases: Empty input yields empty output; very long texts are processed in segments; mixed-language content can produce partial transliteration; unsupported diacritics may be dropped; an invalid preset defaults to Russian.\n\nIndustry/Region & Localization: Default aligns with Russian Cyrillic; locales for Ukrainian and Bulgarian are available via presets; Unicode normalization is preserved; no translation or locale-specific wording is performed.\n\nAssumptions & Exclusions: The tool performs transliteration only, not translation or semantic adaptation; not a detection tool for source language; does not transform non-Latin scripts; excludes pronunciation guidance.