How does Lerzo Player help with language learning?
It adds language-learning tools to film playback: interactive and dual subtitles, offline dictionary lookup, precise line replay, optional explanations from Gemini and study cards for Anki.
Free and open source · macOS
A video player for learning languages on Mac
Watch films in the original language with interactive and dual subtitles. Look up words offline, replay any line, ask Gemini for context and turn useful phrases into Anki cards.
Version 1.2.0 · 38 MB · macOS 14.0 or later · Apple silicon
From watching to understanding, one line at a time
Open a film and its subtitles
Choose the original-language and translation tracks. Lerzo Player works with embedded subtitles and external SRT, ASS and VTT files, and can select tracks using your preferred languages.
Explore the dialogue
Click a word to open its entry from the macOS dictionaries offline. Keep both subtitle tracks on screen, replay the current line or jump precisely to the previous or next one.
Keep what you learn
Use your own Google AI Studio key to ask Gemini about vocabulary, grammar, idioms or context. Save useful lines as study cards and export them to Anki.
Built for the film, not the textbook.
Interactive subtitles
Hovering highlights words. Click one for its entry from the macOS dictionaries — offline, no key needed — or for a translation in the context of the line from Gemini.
Line by line
R plays the current line again, W and E jump to the previous or next one, P pauses at the end of every line and L repeats it. Seeking is exact, even on MKV files of tens of gigabytes.
Dual subtitles
Keep the original and the translation on screen together, or hide the translation and hold TAB to peek at it only when you need to.
Ask the AI
⌘G explains idioms, slang, grammar and the subtext of the scene with Gemini, using your own Google AI Studio key.
Study cards
S saves the line as a card, together with the word you looked up, its meaning and the explanation. The cards collect in their own window and export as a deck for Anki.
Plays everything
MKV, MP4, WebM and whatever else mpv opens, hardware-decoded, HDR included. External .srt, .ass and .vtt subtitles, picked by your preferred languages.
Made for modern Macs and real-world video files
Lerzo Player runs natively on Apple silicon and uses mpv and FFmpeg for hardware-accelerated playback.
- System
- macOS 14 or later on a Mac with Apple silicon.
- Video
- MKV, MP4, WebM and other formats supported by mpv.
- Subtitles
- Embedded subtitle tracks and external SRT, ASS and VTT files.
- Picture
- Hardware decoding and HDR playback on supported displays.
- Interface
- Available in English and Russian.
Private by default. Gemini only when you ask.
Your films and subtitle files stay on your Mac. Lerzo Player has no accounts, analytics or servers of its own. Gemini is optional and uses your Google AI Studio key, stored in the macOS Keychain. Only when you request an explanation does the relevant subtitle text and context go directly to Google's Gemini API. Separately, the app checks the Lerzo update feed on launch and about once a day.
PrivacyFrequently asked questions
Is Lerzo Player free?
Yes. Lerzo Player is free, open-source software released under the GNU GPL v3. It requires no account, and the source code ships with every release.
Which Macs can run Lerzo Player?
Lerzo Player requires macOS 14 or later and a Mac with Apple silicon.
Which video and subtitle formats does it support?
It plays MKV, MP4, WebM and other formats supported by mpv. It works with embedded subtitle tracks and external SRT, ASS and VTT files.
Can I use Lerzo Player offline?
Playback, subtitle navigation, macOS dictionary lookup and study cards work locally. An internet connection is needed when you ask Gemini for an explanation and to check for or download updates.
Can I export study cards to Anki?
Yes. Lerzo Player saves cards locally and exports them as a deck for Anki.
Can I display two subtitle tracks at the same time?
Yes. You can show the original-language and translation tracks together, or hide the translation and hold TAB to reveal it only when needed.
Can I click words in subtitles to see their definitions?
Yes. Click a word to look it up in the offline macOS dictionaries. You can also request an optional contextual translation from Gemini.
How do I repeat one line of dialogue?
Press R to replay the current line, P to pause at the end of each line, or L to loop it. W and E move to the previous or next subtitle line.
Does Lerzo Player work with local video files?
Yes. Lerzo Player is designed for video files stored on your Mac and works with embedded subtitle tracks or external SRT, ASS and VTT files.
Can Lerzo Player play Netflix or YouTube?
No. Lerzo Player is made for local video files and does not open streaming services or YouTube links.
Does Lerzo Player upload my videos or subtitles to Gemini?
It never uploads your video or audio. Only when you request an explanation does the selected subtitle line and the context needed to explain it go directly to Google's Gemini API.
Get Lerzo Player
Signed and notarized. Updates arrive on their own.
Version 1.2.0 · 38 MB · macOS 14.0 or later · Apple silicon