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The LJ Speech Dataset

This is a public domain speech dataset consisting of 13,100 short audio clips of a single speaker reading passages from 7 non-fiction books. A transcription is provided for each clip. Clips vary in length from 1 to 10 seconds and have a total length of approximately 24 hours.

The texts were published between 1884 and 1964, and are in the public domain. The audio was recorded in 2016-17 by the LibriVox project and is also in the public domain.

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Sample Data

The examination and testimony of the experts enabled the Commission to conclude that five shots may have been fired,

Many animals of even complex structure which live parasitically within others are wholly devoid of an alimentary cavity.

File Format

Metadata is provided in transcripts.csv. This file consists of one record per line, delimited by the pipe character (0x7c). The fields are:

  1. ID: this is the name of the corresponding .wav file
  2. Transcription: words spoken by the reader (UTF-8)
  3. Normalized Transcription: transcription with numbers, ordinals, and monetary units expanded into full words (UTF-8).

Each audio file is a single-channel 16-bit PCM WAV with a sample rate of 22050 Hz.


Total Clips13,100
Total Words225,715
Total Characters1,308,678
Total Duration23:55:17
Mean Clip Duration 6.57 sec
Min Clip Duration1.11 sec
Max Clip Duration10.10 sec
Mean Words per Clip17.23
Distinct Words13,821


  • The audio clips range in length from approximately 1 second to 10 seconds. They were segmented automatically based on silences in the recording. Clip boundaries generally align with sentence or clause boundaries, but not always.
  • The text was matched to the audio manually, and a QA pass was done to ensure that the text accurately matched the words spoken in the audio.
  • The original LibriVox recordings were distributed as 128 kbps MP3 files. As a result, they may contain artifacts introduced by the MP3 encoding.
  • The following abbreviations appear in the text. They may be expanded as follows:
    Mrs.Misess (*)

    (*) there's no standard expansion for "Mrs."

  • 19 of the transcriptions contain non-ASCII characters (for example, LJ016-0257 contains "raison d'ĂȘtre").
  • Example code using this dataset to train a speech synthesis model can be found at:
  • For more information or to report errors, please email


  • 1.1 (current release)
    Version 1.0 included 30 .wav files without corresponding annotations in metadata.csv. These have been removed in version 1.1. Thanks to Rafael Valle for spotting this.
  • 1.0
    Initial release


This dataset is in the public domain in the USA (and most likely other countries as well). There are no restrictions on its use. For more information, please see:


This dataset consists of excerpts from the following works:

  • Morris, William, et al. Arts and Crafts Essays. 1893.
  • Griffiths, Arthur. The Chronicles of Newgate, Vol. 2. 1884.
  • Roosevelt, Franklin D. The Fireside Chats of Franklin Delano Roosevelt. 1933-42.
  • Harland, Marion. Marion Harland's Cookery for Beginners. 1893.
  • Rolt-Wheeler, Francis. The Science - History of the Universe, Vol. 5: Biology. 1910.
  • Banks, Edgar J. The Seven Wonders of the Ancient World. 1916.
  • President's Commission on the Assassination of President Kennedy. Report of the President's Commission on the Assassination of President Kennedy. 1964.

Recordings by Linda Johnson from LibriVox. Alignment and annotation by Keith Ito. All text, audio, and annotations are in the public domain.

As this work is in the public domain, you may use it without attribution. However, if you'd like to cite it, please do so by linking to this page or using the following:

@misc{ljspeech17, author = {Keith Ito and Linda Johnson}, title = {The LJ Speech Dataset}, howpublished = {\url{}}, year = 2017 }