Libretto is a macOS app that plays an audiobook while showing the book’s text in sync with the narration. The sentence being spoken is highlighted, and clicking any sentence plays it.

Does it work with my own audiobooks and ebooks?

Yes. Libretto aligns audio and text from files you already own, similar to Kindle’s Whispersync and Audible’s immersion reading, but for your own library and entirely on your Mac.

Which formats are supported?

Audio as .m4b, .m4a or .mp3, with the book text as EPUB or PDF.

Is the ebook mandatory?

No. Without a book text, Libretto transcribes the narration into synced text automatically. The book file gives the best results, so add the EPUB or PDF when you have it.

Is anything uploaded to the cloud?

No. Transcription, alignment and playback all run locally. Your books never leave your Mac.

Libretto — Audiobook Reader with Synced Text for Mac

Listen & read

Libretto is a native audiobook reader for the Mac that shows the book’s own text as you listen. The spoken sentence stays highlighted; past lines dim, upcoming ones wait. Click any sentence to hear it.

Simple, yet precise

The book’s own words

Drop in the EPUB or PDF and Libretto aligns the real text to the narration: the author’s paragraphs, not a rough transcript.

No book file?

Libretto still works as an audiobook player, and can transcribe the narration into synced text. Bilingual audio included.

Always find your place

Bookmarks with notes, recent positions after a stray seek, and resume that snaps to the start of the sentence, never mid-word.

Falls asleep when you do

A sleep timer set by the minute or to the end of the chapter, fading out softly instead of stopping mid-sentence.

Private by design

Your books never leave your Mac. Transcription, alignment and playback all run locally. Nothing is uploaded, ever.

How it works

1
Drop in an audiobook (.m4b, .m4a or .mp3) and, if you have it, the matching EPUB or PDF.
2
Libretto aligns the text to the narration.
3
Read along. The text follows the voice; click any sentence to jump.

Questions

What is Libretto?: Libretto is a macOS app that plays an audiobook while showing the book’s text in sync with the narration. The sentence being spoken is highlighted, and clicking any sentence plays it.
Does it work with my own audiobooks and ebooks?: Yes. Libretto aligns audio and text from files you already own, similar to Kindle’s Whispersync or Audible’s immersion reading, but for your own library and entirely on your Mac.
Which formats are supported?: Audio as .m4b, .m4a or .mp3, with the book text as EPUB or PDF.
Is the ebook mandatory?: No. Without a book text, Libretto transcribes the narration into synced text automatically. The book file gives the best results, so add the EPUB or PDF when you have it.
Is anything uploaded to the cloud?: No. Transcription, alignment and playback all run locally. Your books never leave your Mac.

Libretto

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