# Belin Doc

> Belin Doc is a free AI document translation platform. Translate PDF, DOCX, EPUB, PPTX, XLSX, TXT, JPG, PNG and more while preserving the original layout. Powered by ChatGPT, Claude, Gemini and DeepSeek. Try it without an account for 20 pages; registered accounts get 500 free pages every month, and conversion tools require signing in. Supports 100+ languages.

## Core Translation Tools

- [PDF Translator](https://belindoc.com/tools/free-pdf-translator): Translate PDF files while preserving complex layouts, fonts, and images. Supports scanned PDFs via OCR.
- [Excel Translator](https://belindoc.com/tools/excel-translator): Translate spreadsheet data in .xlsx format while keeping formulas and formatting intact.
- [PPT Translator](https://belindoc.com/tools/ppt-translator): Translate PowerPoint presentations while maintaining the original slide design.
- [EPUB Translator](https://belindoc.com/translate/epub-translator): Translate e-books with chapter structure and formatting preserved.
- [Manga Translator](https://belindoc.com/translate/manga-translator): Translate manga and comics with OCR support for vertical text and speech bubbles.
- [Webtoon Translator](https://belindoc.com/translate/webtoon-translator): Translate webtoons, manhwa, and manhua with OCR for speech bubbles and on-panel sound effects. Preserves vertical-scroll layout and full color.
- [Video Translator](https://belindoc.com/video-translator): Translate video subtitles with AI voiceover generation. No original subtitles required.
- [Subtitle File Translator](https://belindoc.com/video-translator/video-subtitle-translator): Translate SRT subtitle files with timing codes preserved across 100+ languages.
- [Documentary Translator](https://belindoc.com/video-translator/documentary-translator): Broadcast-grade SRT subtitle and script translation for filmmakers and festival submissions.
- [Podcast & Interview Translator](https://belindoc.com/video-translator/interview-podcast-translator): Conversational SRT subtitle and transcript translation for podcasters and interview creators.
- [Blueprint Translator](https://belindoc.com/translate/blueprint-translator): Translate CAD files, engineering drawings, and technical blueprints.
- [Audio Translator](https://belindoc.com/audio-translator): Translate MP3, WAV, M4A, AAC or FLAC recordings into translated subtitles, with optional AI dubbing in the target language; translated subtitles can be edited and re-dubbed. Billed by duration from translation credits, with an estimate shown after upload.
- [Text Translator](https://belindoc.com/text-translator): Paste text and translate it online. Up to 500 words and 1,500 original characters are translated free and instantly; longer texts (up to 100,000 words) are submitted as a task using the same translation credits as documents. Supports glossaries and translation styles; recent tasks are kept for 24 hours.

## Premium Translation Service

- [AI Agent Premium Translation](https://belindoc.com/premium-translation): Higher-quality translation for high-stakes documents (contracts, tenders, annual reports, manuals). A team of specialized AI agents rebuilds document structure, applies a per-document glossary, and self-checks page by page. First page free to preview quality; pay only if the sample works. Priced per document.

## PDF Tools

- [Compress PDF](https://belindoc.com/tools/compress-pdf): Reduce PDF file size without compromising quality.
- [Merge PDF](https://belindoc.com/tools/pdf-merge): Combine multiple PDF files into a single document.
- [Split PDF](https://belindoc.com/tools/pdf-split): Extract specific pages or split a PDF into smaller files.
- [PDF to Word](https://belindoc.com/tools/pdf-to-word): Convert PDF to an editable Word (.docx) file. Keeps text blocks, tables and images in place for digital PDFs; runs OCR on scans so the text becomes editable. Free within your monthly quota — 1 translation credit per page, and scanned pages use OCR without a separate OCR allowance; up to 100 MB and 100 pages per file.
- [PDF to EPUB](https://belindoc.com/tools/pdf-to-epub): Convert PDF documents to reflowable EPUB format for e-readers.
- [PDF to Markdown](https://belindoc.com/tools/pdf-to-md): Convert PDF content to clean, editable Markdown text.

## Developers

- [API Documentation](https://belindoc.com/docs): Open-platform REST API reference — 21 endpoints under `https://belindoc.com/api/external/` for document translation (presigned upload, scanned-PDF check, submit, status, download links, model and language lists), video translation (upload, quota estimate, submit, status, subtitles, rewrite, cancel) and account quota. Authenticate with an `X-Api-Key` header; calls use the same quota, model coefficients and watermark rules as the web app.
- [MCP Server](https://belindoc.com/mcp): Remote MCP server at `https://mcp.belindoc.com/api/mcp` (Streamable HTTP, `Authorization: Bearer <API key>`) that lets MCP clients such as Claude Code and Cursor upload, translate and download documents and videos on the user's Belin Doc account; for clients that cannot set a remote URL with request headers (e.g. Claude Desktop), the same server runs locally over stdio ([belindoc-mcp on PyPI](https://pypi.org/project/belindoc-mcp/)). Same account and quota as the web app.

## AI Models

- [AI Models Overview](https://belindoc.com/ai-models): Overview of supported AI translation models (ChatGPT, Claude, Gemini, DeepSeek).
- [Gemini 3 Integration](https://belindoc.com/ai-models/gemini-3): Gemini 3 model features and translation capabilities.
- [GPT-5-2 Integration](https://belindoc.com/ai-models/gpt-5-2): GPT-5.2 model features and translation capabilities.
- [DeepSeek V4 Translator](https://belindoc.com/ai-models/deepseek-v4): DeepSeek V4 MoE reasoning applied to format-preserving PDF and document translation, with V3.2 available as a cost-efficient option.
- [GPT-4.1 Translator](https://belindoc.com/ai-models/gpt-4-1): GPT-4.1 instruction-following precision for glossary-controlled document translation.

## Popular Language Pairs

- [English to Chinese](https://belindoc.com/translate/english-chinese_simplified)
- [Chinese to English](https://belindoc.com/translate/chinese_simplified-english)
- [English to Japanese](https://belindoc.com/translate/english-japanese)
- [Japanese to English](https://belindoc.com/translate/japanese-english)
- [English to Korean](https://belindoc.com/translate/english-korean)
- [Korean to English](https://belindoc.com/translate/korean-english)
- [English to German](https://belindoc.com/translate/english-german)
- [German to English](https://belindoc.com/translate/german-english)
- [English to Spanish](https://belindoc.com/translate/english-spanish)
- [Spanish to English](https://belindoc.com/translate/spanish-english)
- [Chinese to Japanese](https://belindoc.com/translate/chinese_simplified-japanese)
- [Japanese to Chinese](https://belindoc.com/translate/japanese-chinese_simplified)

## Pricing

- [Pricing Plans](https://belindoc.com/pricing): Free ($0/month), Pro, and Max subscription tiers. Free plan has no page limits per translation.

## FAQs

- [FAQ Index](https://belindoc.com/faqs): All frequently asked questions about document translation.
- [Advantages of AI Document Translation](https://belindoc.com/faqs/advantages-of-ai-document-translation)
- [How to Translate Scanned Documents (OCR)](https://belindoc.com/faqs/how-to-translate-image-or-scanned-documents)
- [How to Generate Bilingual PDFs](https://belindoc.com/faqs/how-to-generate-bilingual-pdf)
- [How to Batch Translate Documents](https://belindoc.com/faqs/how-to-batch-translate-documents)
- [How to Translate Very Large PDFs](https://belindoc.com/faqs/how-to-translate-very-large-pdf)
- [How to Add Glossaries During Translation](https://belindoc.com/faqs/how-to-add-glossary-in-document-translation)
- [Why PDF Has Two Text Layers After Translation](https://belindoc.com/faqs/why-pdf-has-two-layers-of-text-after-translation)
- [Engineering PDF Translation Difficulties](https://belindoc.com/faqs/engineering-pdf-translation-difficulties)
- [Private Deployment Solution](https://belindoc.com/faqs/belindoc-private-deployment-solution)
- [Video Translation Difficulties](https://belindoc.com/faqs/difficulties-in-online-video-translation)
- [High-Quality Video Simultaneous Translation](https://belindoc.com/faqs/how-to-achieve-high-quality-video-translation)

## Blog

- [Top 10 Best Document Translation Tools in 2026](https://belindoc.com/blog/top-10-document-translation-tools-2026)
- [How to Use AI to Translate PDF, Word & PPT](https://belindoc.com/blog/how-to-use-ai-translate-documents)
- [Engineering Drawing Translation Guide](https://belindoc.com/blog/engineering-drawing-translation-guide-maintain-layout)
- [Translate DWG & DXF Files Online: Native CAD Translation Without PDF Export](https://belindoc.com/blog/translate-dwg-dxf-cad-files-online)
- [GPT-5 Mini vs Gemini 2.5: AI Translation Benchmark 2025](https://belindoc.com/blog/ai-translation-model-benchmark-gpt5-vs-gemini)
- [Scanned PDF Translation Errors: Complete OCR Fix Guide](https://belindoc.com/blog/translating-scanned-pdf-ocr-guide-fix-errors)
- [How to Translate EPUB in 2026](https://belindoc.com/blog/how-to-translate-epub-with-belin-doc-2026)
- [How to Translate a Korean Webtoon (Manhwa & Manhua) to English in 2026](https://belindoc.com/blog/how-to-translate-webtoon-to-english)
- [Translating Vertical Text in Japanese/Chinese PDFs](https://belindoc.com/blog/translate-vertical-text)
- [Video Translation Guide: Subtitles & AI Voiceover](https://belindoc.com/blog/online-video-translation-guide)
- [How to Translate a Recording: Subtitles or AI Dubbing?](https://belindoc.com/blog/how-to-translate-audio)
- [How to Translate Long Text: Free Limits, Word Count, Models](https://belindoc.com/blog/translate-text-online-guide)
- [GPT-5.2 Document Translation Review](https://belindoc.com/blog/gpt-5-2-document-translation-review)
- [Gemini 3 Translation Performance Review](https://belindoc.com/blog/gemini-3-translation-performance-review)
- [BelinDoc Troubleshooting: Double Text, Failures, Formatting](https://belindoc.com/blog/belindoc-translation-faq-troubleshooting)
- [How to Translate Excel Files While Keeping Formulas](https://belindoc.com/blog/how-to-translate-excel-files-keep-formulas)
- [AI Novel Translation Complete Guide 2026](https://belindoc.com/blog/ai-novel-translation-guide-2026)
- [Editable PDF Translation and Post-Editing Guide](https://belindoc.com/blog/belindoc-pdf-translation-post-editing)

## Changelog

- [Changelog](https://belindoc.com/changelog): Product version history and feature releases since launch (v1.0.0, July 26, 2025).

## Legal

- [Privacy Policy](https://belindoc.com/privacy): Data handling policy. Uploaded files are deleted within 24 hours after translation.
- [Terms of Service](https://belindoc.com/terms): Usage terms and restrictions. Service governed by PRC law.
- [Business Cooperation](https://belindoc.com/business-cooperation): Partnership, affiliate, and enterprise opportunities.

## Site Resources

- [Sitemap](https://belindoc.com/sitemap.xml): Complete XML sitemap index for all pages across 9 language locales.
- [robots.txt](https://belindoc.com/robots.txt): Crawler access rules (all crawlers allowed).