The translation tool that Questsoft abandoned. Rebuilt from scratch. Built to last.
Download · Plugin Guide · 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. 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 |
| Quick Translate popup | Ctrl+Q on any selected text — popup with result, no main window needed |
| 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 |
| 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 |
| 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 |
| 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 |
| 30+ themes | Dark and light via FlatLaf, with animated transitions — drop any IntelliJ .theme.json into the themes/ folder to add more |
| Portable | Runs from any folder, all data lives next to the JAR |
Requires Java 11 or later — download from Adoptium if you need it.
- Download
QTranslate-<version>.zipfrom Releases - Unzip anywhere
- Run
QTranslate.jar
QTranslate/
├── QTranslate.jar ← double-click, or: java -jar QTranslate.jar
├── plugins/
│ ├── google-services-plugin.jar
│ ├── bing-services-plugin.jar
│ └── ai-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
└── ...
Google, Bing, and AI plugins are included. Add your API keys in Settings → Plugins → [plugin] → Configure.
Getting "This application requires a Java Runtime Environment"? Java isn't installed or
JAVA_HOMEisn't set. This video covers the full process: ▶ How to Install Java JDK and Set JAVA_HOME (first 7 minutes)
Build from source → Building from Source
- 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+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 → select .jar → Enable → Configure → assign in Services & Presets
Full guide → Installing Plugins
Built a plugin? Publish it on GitHub with the
qtranslate-plugintopic and aqtranslate-plugin.jsonin your repo — it will appear automatically in QTranslate's built-in marketplace. → Plugin publishing guide
| Plugin | Services | Author |
|---|---|---|
| (be the first — it's 50 lines of Kotlin) |
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())
}The bundled Google, Bing, and AI plugins are fully open source in plugins/ — they're the best real-world reference for auth, language mapping, error handling, and settings.
Full guide → Creating a Plugin
QTranslate ships with 13 languages built in:
Arabic · Bengali · Chinese · English · French · German · Hungarian · Italian · Japanese · Portuguese · Russian · Spanish · Turkish
Want another language? Copy languages/en.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/* ← Google, Bing, AI, community plugins
:plugins/common ← shared HTTP client, JSON, language utilities
Guide → Architecture
If QTranslate saves you from Alt-Tabbing to Google Translate a dozen times a day, a coffee is always appreciated!
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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