Translate entire PDFs.
Every page, perfect.
Long documents break AI translators. TransDocs smart-chunks your PDFs by chapter, carries context forward, and delivers professional translations from start to finish.
10 free pages every month. No credit card required.
AI translation breaks on long documents
Paste a 200-page PDF into ChatGPT and watch it choke. The model hits its context limit, silently drops paragraphs, and the translation degrades into nonsense halfway through.
- Context window exceeded -- content silently dropped
- Translation quality degrades after page 20-30
- Inconsistent terminology across chapters
- Manual copy-paste into ChatGPT, chapter by chapter
- No way to track progress on large documents
- Smart chunking splits by chapters -- every page translates
- Context carried forward so terminology stays consistent
- Works on 10-page papers and 500-page books alike
- One-click upload, automatic processing, done
- Real-time streaming progress for every chapter
Three steps to a perfect translation
Upload, configure, download. No manual splitting, no copy-pasting, no babysitting.
Upload Your PDF
Drag and drop any PDF up to 50 MB. We extract text while preserving the document's chapter structure and hierarchy.
Choose Language & Model
Select your target language and preferred AI model. Source language is auto-detected. Adjust chunk strategy if needed.
Download Translation
Watch real-time progress as each chapter translates. Download your professionally translated PDF the moment it finishes.
Built for serious document translation
Not another wrapper on Google Translate. TransDocs understands document structure and uses frontier AI models.
Smart Chunking
Automatically splits PDFs by chapters and headings. Each chunk carries forward context so translations stay coherent across hundreds of pages.
13 Languages
Translate between English, Chinese, Japanese, Korean, Spanish, French, German, Portuguese, Vietnamese, Thai, Arabic, Russian, and more.
Multiple AI Models
Choose from Claude Sonnet, Claude Opus, GPT-4o, and Gemini Flash. Pick the best model for your language pair and budget.
Real-time Progress
Watch every chapter translate live with streaming progress. No staring at a spinner wondering if it crashed.
BYO API Key
Bring your own OpenRouter key and pay only for tokens at provider rates. No middleman markup, complete cost transparency.
Secure & Private
Documents are processed in memory and never stored on our servers. Your files are deleted immediately after translation completes.
Simple, transparent pricing
Start free. Upgrade when you need more pages. Cancel anytime.
- 1,000 pages/month
- All models including Opus & GPT-4o
- Priority processing
- No watermark
- Translation history
- Priority support
Need more pages? Add-on pages available at $0.05/page on any paid plan.
Frequently asked questions
Why do other AI translators fail on long PDFs?
Most tools feed the entire document into one AI prompt. When a PDF exceeds the model's context window, the AI silently drops content, hallucinates, or produces garbled output. TransDocs solves this by intelligently splitting your document into chapter-sized chunks, each carrying context from prior sections, so every page translates perfectly regardless of total length.
What languages are supported?
TransDocs supports 13 languages including English, Traditional Chinese, Simplified Chinese, Japanese, Korean, Spanish, French, German, Portuguese, Vietnamese, Thai, Arabic, and Russian. Source language is auto-detected, and you can translate between any combination of supported languages.
How does the BYO API Key option work?
If you have an OpenRouter API key, you can enter it in your account settings to use your own API credits for translations. You pay only the provider's token rates with zero markup from us. This is perfect for power users who want unlimited translations at cost.
Is my document data safe?
Yes. Your PDFs are processed in-memory on our servers and are never written to disk or stored in a database. The original file and translated output are deleted from memory immediately after you download the result. We use encrypted connections (TLS) for all data transfers.
What PDF formats work best?
TransDocs works with any text-based PDF. Scanned image PDFs (without OCR text layers) are not currently supported. For best results, use PDFs with clear heading structure — our smart chunker uses headings, font sizes, and page breaks to find optimal split points.
Can I translate a 500-page book?
Absolutely. That's exactly what TransDocs is built for. Our smart chunking engine handles documents of any length by breaking them into coherent chapter-sized pieces, translating each with full context, and reassembling the result. A 500-page book typically takes 10-20 minutes depending on the AI model you choose.
Ready to translate your first document?
Join thousands of researchers, students, and professionals who trust TransDocs for accurate, full-length PDF translations.
10 free pages every month. No credit card required.