Tools

Translates full PDF papers while preserving formulas, charts and layout (command pdf2zh), outputting monolingual and side-by-side bilingual PDFs. Uses Google Translate by default and can switch to DeepL, OpenAI and others; also runs as an MCP server.

Offline speech transcription and translation based on Whisper; audio never leaves your machine. buzz add exports lectures, interviews and meeting recordings to TXT, SRT or VTT. pip install needs Python 3.12 and FFmpeg; a desktop app is also available. Check transcripts manually.

CLI version of the VideoCaptioner subtitle assistant: transcribes courses, lectures and interviews, uses an LLM to segment, proofread and translate, then burns subtitles into the video. Free ASR and Bing translation work out of the box; LLM refinement needs an API key. Python 3.10 to 3.12.

Open-source grammar, spelling and style checker for 20+ languages including English, German, French, Spanish and Portuguese. Proofread drafts in bulk from the CLI or run a local HTTP checking server for agents. For writers, translators and language teachers. Needs Java 17 (Homebrew includes it).

Uses LLMs to translate EPUB, TXT, Markdown, SRT, PDF and other files into side-by-side bilingual editions, via OpenAI, Anthropic, Gemini and other APIs or DeepL and Google Translate. LLM APIs need your own key or a Codex subscription. Only translate content you have rights to.

PDF translation CLI for research papers that preserves formulas and layout as much as possible, producing bilingual side-by-side or translation-only PDFs. Needs an OpenAI-compatible API (local Ollama works too); currently focused on English to Chinese.

Extracts subtitles burned into videos to SRT or TXT, with all OCR done locally in 87 languages. Mainly a GUI (with batch mode); the CLI backend/main.py reads the video path and subtitle area from stdin. Needs Python 3.12+ and PaddlePaddle; paths cannot contain spaces or Chinese characters.

Lingo.dev's official CLI: lingo push sends JSON, YAML, Markdown, PO, XLIFF, Android/Xcode strings and other files from your repo to its LLM localization engine, and lingo pull brings translations back; CI-ready. Needs a Lingo.dev account; usage-based pricing with a free sandbox.

Pluggable natural-language linter that checks Markdown and plain text for wording, punctuation and terminology consistency like code, with auto-fix, and can also run as an MCP server. Rules are installed separately, mostly for Japanese and English; requires Node.js 20+.

PDFMathTranslate 2.x (command pdf2zh_next), built on BabelDOC: translates papers and other PDFs while keeping formulas, charts, TOC and annotations, outputting translated and bilingual side-by-side versions. Uses a free translation channel by default, or your own OpenAI, DeepSeek or other API key.

Helps app marketers and translators plan multilingual App Store listings: prioritize countries, research keywords per market, rewrite title, subtitle, keywords and description, and flag screenshot and cultural issues rather than translating literally. Guidance only, no account needed.

Translation management for Ruby/Rails: statically analyzes code to find missing and unused keys, normalizes locale files, fills gaps via Google Translate, DeepL or OpenAI, and exports CSV for translators. Requires the i18n gem (Rails default) and Bundler; machine translation needs an API key.

AI localization: deploy the server to your own Vercel account (Postgres and AI Gateway included; enable deployment protection afterwards), then run npx languine@selfhosted translate to translate locale files with LLMs. A GitHub Action can open PRs. Needs a Vercel account and Node.js.

Translates a video's SRT subtitles into other languages and generates AI voice lines synced to the timings, producing translated subtitles and dubbed audio tracks. Needs Python, FFmpeg and Google Cloud, Azure, DeepL or ElevenLabs API keys; configure the ini files, then run python main.py.

One plugin bundling skills and subagents for deep research, fixing GitHub issues and reviewing PRs, Codex handoff, Gemini or GPT image generation, translation and YouTube transcript extraction, plus settings.json templates for various providers (manual setup). Some skills need API keys.

Chinese-English translation and word lookup in the terminal: one command shows definitions, phonetics and examples from iCiba, Youdao and an LLM. No API key needed (built-in free LLM proxy), or use any OpenAI-compatible model. Needs Node.js 20+; queries are sent to these online services.

Sets up and audits i18n for React, Next.js and Vue apps: replaces hard-coded strings with message keys, checks that English and Chinese keys are complete and consistent, and verifies plurals and date and number formats, with a key audit script. Needs a local codebase and Python.

Local LLM-powered document translator for PDF, Word, Excel, EPUB, SRT subtitles and more; Word and Excel keep their formatting, glossaries can be built automatically, and agents can submit jobs via MCP. Needs uv and an OpenAI-compatible API key; translated PDFs lose the original layout.

The standard machine translation scorer: computes BLEU, chrF and TER with significance tests and downloads public test sets such as WMT, to compare engines or prompts. Needs Python 3.9+ and reference translations; automatic metrics are a rough screen, so final copy still needs human review.

Creates and edits local CapCut (JianYing) drafts from the terminal: rough cuts on silence, styled subtitles and multilingual versions, still editable track by track in CapCut. Needs Node 18+ and desktop CapCut; subtitles need Whisper, translation an Anthropic key. No encrypted drafts. Unofficial.

Community App Store localization skill (not from Apple): uses the asc CLI and an LLM to translate listing copy such as description, keywords, subtitle and release notes into many languages and sync it to App Store Connect. Needs asc set up and authorized; proofread before submitting.

Open-source video translation and dubbing: transcribes lectures, courses and other videos, translates them into one of 33 languages, synthesizes a dub aligned to the picture, and can export SRT subtitles. Needs Python 3.10+, FFmpeg, the violin CLI and a pay-as-you-go Together AI API key.

General Translation's gt CLI: a wizard sets up i18n for React, Next.js and similar apps, then sends UI strings and JSON, YAML or Markdown files for AI translation and writes them back, with CI support. Needs a Node.js project and a General Translation API key (free sign-up, usage-based pricing).

Open-source toolkit widely used in localization: converts between PO, XLIFF, TMX, CSV, subtitle and other translation formats, counts words, runs 40+ translation checks with pofilter and extracts frequent terms with poterminology. Needs Python 3.11+.