Langzapp combines professional-grade document handling with offline AI models — giving you translation quality without cloud dependency.
Format-aware translation preserves structure, layout, and styling across all supported file types.
Translates paragraphs, headings, tables, and footers. Layout and styles preserved via Microsoft Word COM integration.
Extracts text from PDF, translates, and overlays translated content. Handles multi-page documents cleanly.
Slide-by-slide translation of text frames and notes. URLs and non-translatable content automatically skipped.
Cell-by-cell translation across multiple sheets. Formulas left untouched — only text cells translated.
Translates subtitle text while keeping all timing codes intact. Supports SRT and WebVTT formats.
Translate plain text, Markdown, and other structured text files. Markdown structure preserved during translation.
Langzapp processes everything locally. There are no API calls to external servers during translation. Confidential contracts, legal documents, medical records, and financial reports stay entirely on your Windows PC.
All translation happens on your hardware using local AI models. No data transmitted. Ever.
Best-in-class open-source models, optimised for CPU inference on standard Windows hardware.
Helsinki-NLP OPUS-MT models fine tuned and quantized. Fast inference, excellent quality for European language pairs.
Alibaba's Qwen models provide high-quality Chinese and Korean translation, handling complex sentence structures accurately.
Specialized model for Japanese ↔ English translation. Handles kanji, hiragana, katakana and complex grammatical structures with high fidelity.
AI4Bharat's IndicTrans2 — the most accurate neural translation model available for official Indian languages. Exceptional quality for technical, legal, and general-purpose content.
EUA and Asia plans from $29/year. Indic plans from ₹900/year. Pick the plan that matches your languages — each includes every document format.
Download the free trial — no account needed. Subscribe when you're ready.