KenjaSub Video Subtitle Editor
AI transcription & translation
Only for Mac
$19.99
Mac
Turn any video into bilingual subtitles — on-device transcription, translation with your own AI model or Apple's engine, then frame-accurate polish in the studio.
"Kenja" is Japanese for "sage" — the wise one. It is also our mission: to build smarter software. KenjaSub is our video subtitle editor for Mac. It turns any video into polished bilingual subtitles — transcribed on device, translated in context, and refined frame by frame in the built-in studio.
THREE TABS, ONE WORKFLOW
• Auto — Drop several videos, get subtitle files. Speech recognition, translation and export run as one batch queue with per-video overrides, live progress and one-click retry.
• Refine — A full studio on top of your video: an mpv-based player that opens MKV, WebM and AVI natively, a synchronized cue list with waveform, undo/redo, split and merge, and instant export to SRT or WebVTT.
• Models — Bring your own key. Add any OpenAI-compatible provider (OpenAI, DeepSeek, OpenRouter, Ollama, LM Studio or a custom endpoint). Keys live in your Mac's Keychain — never in plain files.
TRANSLATION THAT READS THE WHOLE FILM
Subtitles are translated in context windows with the surrounding lines, so pronouns, tone and recurring names stay consistent across the whole video. Pick a register that fits your channel — Natural, YouTube, Conversational, Professional, Documentary or Literal. If something is off (a mismatched source language, a model answering in the wrong language), KenjaSub stops and tells you instead of silently saving a bad file.
CHAT WITH YOUR SUBTITLES
The built-in AI assistant edits subtitles conversationally. Ask it to retranslate a scene, shorten a line, or fix a name. You choose how it touches your project: "Ask before changes" stages every edit as a reviewable diff first, or "Edit automatically" applies instantly with one-click undo for any chat turn. Long conversations compress automatically so you never lose context.
PRIVATE BY DEFAULT
• Transcription runs entirely on device with Apple's SpeechAnalyzer — your audio never leaves your Mac.
• Choose the Local engine and translation runs on device too, via Apple's Translation framework.
• AI features are strictly bring-your-own-key: subtitle text is sent only to the provider you configured, only when you choose that engine.
• No accounts. No analytics. No tracking.
MADE FOR VIDEO PEOPLE
• Bilingual SRT import with automatic language detection — your existing translations come along.
• Reading-speed and line-length checks keep subtitles readable on screen.
• Batch output to any folder, with the Finder reveal when the run completes.
REQUIREMENTS
macOS 26 or later. On-device transcription and translation use Apple's neural frameworks (Apple Silicon recommended).
KenjaSub does not include AI model access; AI translation and the assistant require an API key from a provider you choose.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
New in the subtitle studio:
• Open an SRT alone — editing, the AI assistant and export all work without a video.
• Type exact timecodes, split, merge or shift cues; Undo (⌘Z) works everywhere.
• Chat with the AI about selected cues: Shift-click a range, right-click, Ask AI.
• Dropping a video and an SRT together still jumps straight into the studio.
• Closing with unexported edits now reminds you to export — your original files are never modified.
The developer, 伟 黄, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- 伟 黄
- Size
- 7.3 MB
- Category
- Photo & Video
- Compatibility
Requires macOS 26.0 or later and a Mac with Apple M1 chip or later.
- Mac
Requires macOS 26.0 or later and a Mac with Apple M1 chip or later.
- Mac
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © @wei huang
