PDFMathTranslate

1. What is PDFMathTranslate?

PDFMathTranslate (also called pdf2zh) is a free tool that translates a whole PDF into another language while keeping the layout: math formulas, charts, tables, the table of contents and annotations stay where they were. It was built for scientific papers and was presented at the EMNLP 2025 conference. You feed in one PDF and get back two: one with only the translated text and one bilingual copy.

It replaces copying paragraphs into a translator and pasting them back (which wrecks the formatting), or paid document-translation services. The default translation service is Google, so no API key is needed. The project uses the AGPL-3.0 license.

A good fit if:

• You read English papers, technical docs or textbooks as PDFs and want a translation that looks like the original.
• You want a bilingual copy to compare paragraph by paragraph.
• You do not want to pay for or sign up to a document-translation service.

Not a fit if:

• You need verified, polished Vietnamese output. The README and the project's GUI docs do not list Vietnamese among the officially supported languages of the web interface (ten are listed: English, Simplified and Traditional Chinese, French, German, Japanese, Korean, Russian, Spanish, Italian). The command line accepts Google language codes, so vi is a valid code, but test a short file first.
• Your PDF is a fully scanned image. The OCR support (reading text from images) is marked experimental.
• You are translating confidential documents. The default service sends the text to Google, so think before you use it.

2. What you need

There are three routes, from easiest to hardest:

1. Use it on the web, install nothing. You need a browser and internet. The README points to https://pdf2zh.com/ as a "Public free service". Resources are limited, so do not abuse it.
2. Windows build (.zip). You need 64-bit Windows. If it will not open, also install the "Microsoft Visual C++ Redistributable" (a bundle of components many Windows programs need): vc_redist.x64.exe from https://aka.ms/vs/17/release/vc_redist.x64.exe, as the README suggests.
3. Install with Python or Docker. You need Python (a programming language, from https://www.python.org/downloads/) version 3.11 to 3.12, or Docker (software that runs apps in ready-made "boxes") from https://www.docker.com/.

No account and no API key are needed with the default Google service. On the first run the program downloads an AI model that detects page layout, so you need internet and some free disk space (the docs give no exact size).

3. Step-by-step setup

Way A: Use it on the web

1. Go to https://pdf2zh.com/.
2. Drop your PDF in, choose the target language and translate. File-size and usage limits are set by the site, so check them there.

Getting a translated PDF to download means it worked.

Way B: Windows .zip (no Python needed)

Step 1: Download

Go to https://github.com/PDFMathTranslate/PDFMathTranslate/releases and download pdf2zh-v1.9.11-win64.zip (v1.9.11 is the latest release on the Releases page, published July 2025). There is also a with-assets file that bundles the model, useful if you cannot download it at run time.

Step 2: Unzip and run

Unzip it, then double-click pdf2zh.exe. If Windows cannot open it, install vc_redist.x64.exe as described in section 2 and try again.

A window or a browser page opening means it is working.

Way C: Install with Python

Step 1: Install Python

Install Python 3.11 or 3.12 from https://www.python.org/downloads/. On Windows, tick "Add python.exe to PATH" on the installer's first screen.

Step 2: Install pdf2zh

Open Terminal (macOS/Linux) or PowerShell (Windows) and run:

pip install pdf2zh

Finishing with no red errors means success. (The README also shows a uv route: pip install uv, then uv tool install --python 3.12 pdf2zh.)

Step 3: Open the browser interface

pdf2zh -i

If the browser does not open by itself, go to http://localhost:7860/. Drop a PDF in the window and click Translate.

Way D: Docker

docker pull byaidu/pdf2zh
docker run -d -p 7860:7860 byaidu/pdf2zh

Then open http://localhost:7860/.

4. First use

The quickest test is the command line, in the folder that holds your PDF:

pdf2zh document.pdf

Per the README, it creates two files in the current folder: document-mono.pdf (translation only) and document-dual.pdf (bilingual).

Important: The default target language is Simplified Chinese (the README uses -lo zh in its example, and the GUI docs list the default as "Simplified Chinese"). To pick another language, add -li (source) and -lo (target), for example:

pdf2zh document.pdf -li en -lo vi

Language codes follow Google and DeepL. Vietnamese is not on the official GUI list, so try a short file, check the bilingual copy, and only then translate long documents. To translate only some pages, add -p 1 (page 1 only).

5. Common problems and fixes

Symptom	Likely cause	Fix
pdf2zh or pip says "command not found" / "not recognized"	Python is not installed or not on PATH	Reinstall Python, tick "Add python.exe to PATH", open a new terminal
Install complains about the Python version	The README requires Python 3.11 to 3.12	Install Python 3.12 and rerun
Stuck downloading the model	In some regions the model host (Hugging Face) is unreachable	Set HF_ENDPOINT=https://hf-mirror.com as the README describes (PowerShell: $env:HF_ENDPOINT = "https://hf-mirror.com"), or use the with-assets zip
The translation comes out in Chinese	The target language was not set	Add -lo vi (or another language code)
pdf2zh.exe will not open on Windows	Missing Visual C++ components	Install vc_redist.x64.exe and retry
Port 7860 is already in use	Another program is using it	Add --serverport 7861 and open the new port

If it still fails, see the FAQ in the project wiki: https://github.com/PDFMathTranslate/PDFMathTranslate/wiki

6. Uninstall / update

• Python: uninstall with pip uninstall pdf2zh; update with pip install -U pdf2zh. If you installed with uv, use uv tool uninstall pdf2zh.
• Windows zip: delete the unzipped folder; to update, download the newer zip.
• Docker: stop and remove the container in Docker Desktop; to update, run docker pull byaidu/pdf2zh.

7. FAQ

Does it cost money? The program is free. The default translation service (Google) needs no key. If you choose another service such as OpenAI or DeepL, you need your own API key and the provider may charge you.

Does my data go anywhere? With the default service, the text in your PDF is sent to the translation service. The project also supports local services such as Ollama (see the advanced docs) if you want to keep things on your machine.

Do I need internet? Yes: to download the model the first time and to call the translation service.

Is it only for scientific papers? The project targets scientific papers, though the README describes it as a layout-preserving PDF translator. Try it on your own file first.

Any other PDF tools on githot? Yes: BentoPDF (PDF tools in your browser) at https://www.githot.io.vn/en/repo/bentopdf, and RetainPDF at https://www.githot.io.vn/en/repo/wxyhgk-retain-pdf.