The translation tool that Questsoft abandoned. Rebuilt from scratch. Built to last.
Download · Plugin Guide · Build from source · Support · Contributing · Wiki
The original QTranslate by Questsoft was the best desktop translation tool on Windows — until development stopped, APIs broke, and users were left with a dead app.
This is a full rewrite in Kotlin with one core design change: everything is a plugin. Translation engines, OCR, TTS, spell checkers, dictionaries — all separate JARs you install at runtime. When a service changes its API or shuts down, you swap the plugin. The app keeps running.
Select text anywhere → press Ctrl+Q → translation appears instantly. That's the core of it.
Quick Translate — select text in any app, press Ctrl+Q
For longer work: open the main window, type or paste, translate. Switch engines in one click. Translate a document while preserving its structure. Run OCR on a screenshot. Listen to pronunciation. Check spelling. Browse history. All from the keyboard, all without opening a browser.
 Main window — translate, summarize, rewrite, spell check, browse history |
 RTL support — full layout mirroring for Arabic, Hebrew, Farsi, and more |
 Compact layout, light theme — tabbed view, fits any workflow |
 Settings — Services & Presets — configure engines, presets, and API keys |
 Side-by-side layout — source and translation in parallel columns |
 Document translation — DOCX, PDF, TXT, SRT and VTT, structure preserved |
| Quick Translate popup | Ctrl+Q on any selected text — popup with result, no main window needed |
| Image search | Ctrl+Shift+Q on any selected word — a grid of reference pictures from Wikimedia Commons, enlarged in place, licence shown and source page a click away. For the words a definition alone does not settle |
| Instant translation | Translates as you type with configurable debounce |
| Inline replace | Ctrl+Shift+T — translates selected text and pastes the result back in place |
| Backward translation | See the round-trip result alongside the main output — spots awkward phrasing instantly |
| Summarize | Get a condensed version of long text, configurable length |
| Rewrite | Rewrite in a different style: Formal, Casual, Concise, Detailed, or Simplified |
| Translation history | Full undo/redo through every past translation |
| Translation rules | Auto-correct source text before translating — fix common mistakes, expand abbreviations, normalize input |
| Document translation | Translate DOCX, PDF, TXT, SRT, and VTT files with progress and cancellation; DOCX structure and subtitle timing are preserved |
| Screen OCR | Draw a rectangle anywhere on screen — translate, copy text, copy image, or save; re-crop without closing |
| Spell checking | Live underlines as you type, click a suggestion to apply |
| Remove line breaks | Strips newlines from pasted text so PDF content translates as sentences |
| Language filter | Pin 3–4 target languages so the picker isn't overwhelming |
| Cycle languages | Ctrl+L steps through pinned languages without touching the mouse |
| Plugin system | Install .jar plugins at runtime — no restart, no reinstall |
| Plugin manager | Search and filter installed plugins, inspect metadata and errors, configure or toggle services inline, and install by file or drag-and-drop |
| Service presets | Save different engine combinations for different contexts |
| Google Services | Translator, TTS, OCR, Spell Checker, Dictionary — included |
| Bing Services | Translator, TTS, Spell Checker — included |
| AI Services | Translator, Summarizer, Rewriter, Spell Checker, Dictionary, Vision OCR — via OpenRouter (300+ models, one API key) — included. Setup guide |
| Free translation choices | Mozhi, MyMemory, DeepL web fallback, Reverso, and Yandex Web work without an API key; unofficial endpoints may change or be rate-limited |
| Fully offline & private | Point AI Services at a local Ollama or LM Studio server, or use a self-hosted LibreTranslate instance. No account, no API key, no per-word cost, and nothing leaves your machine — for work under an NDA, proprietary code, or anything else that cannot go to a cloud service. Setup guide |
| Reference services | Wikipedia and Wiktionary lookups, and Wikimedia Commons image search, through official MediaWiki APIs |
| CSV dictionary | Point it at your own CSV — a glossary, an abbreviation list, a table of error codes, a set of study notes — and look terms up in it. Which columns hold the term and its meaning is configurable, and nothing leaves your machine |
| Three layouts | Classic (stacked), Side-by-side, Compact (tabbed) |
| Global hotkeys | Every action is bindable, configurable as global or app-local |
| RTL support | Full layout mirroring for Arabic, Hebrew, Farsi, and more |
| QTranslate Light & Dark | Purpose-built defaults with OS light/dark synchronization, plus 30+ FlatLaf themes and custom IntelliJ .theme.json support |
| Portable | Runs from any folder, all data lives next to the JAR |
All downloads live on the latest release page.
| Your platform | Download | Java required |
|---|---|---|
| Windows | QTranslate-<version>-windows-x64.zip |
No — Java is included |
| macOS / Linux | QTranslate-<version>.zip |
Java 11+ |
| Any (app only, no plugins) | QTranslate-App-<version>.jar |
Java 11+ |
Every download already contains all bundled plugins, languages, and themes. Pick one — you do not need the others.
- Download
QTranslate-<version>-windows-x64.zip - Extract to a writable folder
- Run
QTranslate.exe
No Java installation needed — the package ships its own trimmed runtime.
- Install Java 11 or later (Temurin recommended)
- Download and extract
QTranslate-<version>.zip - Run
QTranslate.jar, orjava -jar QTranslate.jarfrom a terminal
QTranslate/
├── QTranslate.jar ← double-click, or: java -jar QTranslate.jar
├── plugins/
│ ├── google-services-plugin.jar
│ ├── bing-services-plugin.jar
│ ├── mozhi-services-plugin.jar
│ └── ...
├── themes/
│ └── kokedera.theme.json ← community theme included; drop more .theme.json files here
├── languages/
│ ├── ar-SA.toml
│ ├── zh-CN.toml
│ ├── de-DE.toml
│ └── ...
├── icons/
│ ├── material-symbols/
│ ├── tabler/
│ ├── phosphor/
│ └── heroicons/ ← extra icon sets; drop a set's folder in to add it
└── THIRD_PARTY_LICENSES/
├── Lucide-ISC.txt
├── MaterialSymbols-Apache-2.0.txt
└── ... ← licenses for every bundled font, icon set and theme
Bundled plugins: Google, Bing, AI Services, DeepL, Mozhi, MyMemory, LibreTranslate Local, Reverso, Yandex Web, Wikimedia Reference, and CSV Dictionary. Configure a service from the service selector or Settings → Plugins.
Individual plugin JARs are also attached to each release. They are only for adding or updating a single plugin in an existing install — you do not need them for a fresh setup.
Getting "This application requires a Java Runtime Environment"? Java isn't installed or
JAVA_HOMEisn't set — or use the Windows package, which needs neither. ▶ How to Install Java JDK and Set JAVA_HOME (first 7 minutes)
Build from source → Building from Source
Preparing a release → Release Guide
- Launch
QTranslate.jar— it starts in the system tray - Select text anywhere on screen
- Press
Ctrl+Q— Quick Translate popup opens with the result ready - Press
Ctrl+D— open the Dictionary for the selected word - Press
Ctrl+Shift+Q— see pictures of the selected word - Press
Ctrl+E— listen to the selected text - Press
Ctrl+I— draw a screen region to OCR and translate
Open Settings (gear icon) to configure API keys, themes, hotkeys, and service presets.
Installing a plugin: Settings → Plugins → Install Plugin, or drop a plugin JAR onto the plugin panel. Review its details, enable it, configure it, then assign its services under Services & Presets.
Full guide → Installing Plugins
The in-app catalog and independent plugin updater are planned but are not available yet. Until then, install only JARs from publishers you trust and verify any checksum they provide.
Built a plugin? Publish its source, release JAR, compatibility range, and checksum. See the plugin publishing guide.
A minimal translator is ~50 lines of Kotlin. No framework, no registration — implement a few interfaces, build a fat JAR, install it through the UI.
class MyPlugin : Plugin<PluginSettings.None> {
override val id = "com.example.my-plugin"
override val name = "My Plugin"
override val version = "1.0.0"
override fun getSettings() = PluginSettings.None
override fun getServices() = listOf(MyTranslatorService())
}All bundled plugins are open source under plugins/. They provide real-world examples of authentication, no-key services, local endpoints, throttling, language mapping, batch translation, dictionaries, and structured errors.
Full guide → Creating a Plugin
QTranslate ships with 14 languages built in:
Arabic · Bengali · Chinese · English · French · German · Hungarian · Italian · Japanese · Portuguese · Russian · Spanish · Turkish · Vietnamese
Want another language? Copy languages/en-GB.toml, rename it to your language code, translate the values. No code needed.
Guide → Adding a Language
Clean Architecture + MVI. Nothing leaks between layers:
:api ← plugin interfaces — plugins only depend on this
:core ← business logic, use cases, MVI stores
:ui-swing ← Swing UI, Renderable<State> components
:app ← composition root
:plugins/* ← independently packaged service implementations
:plugins/common ← shared HTTP client, JSON, language utilities
Guide → Architecture
QTranslate is free and open source. If it saves you time, support helps with maintenance, compatibility testing, and future releases.
Bug fixes, features, translations, docs, and plugins all welcome. Look for good first issue for well-scoped starting points.
Built with Kotlin · FlatLaf · Ktor · Coroutines
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