Common Voice Spontaneous Speech 3.0 - Breton

Brezhoneg — Breton (br)

This datasheet is for sps-corpus-3.0-2026-03-09 of the Mozilla Common Voice Spontaneous Speech dataset for Breton [Brezhoneg - br]. The dataset contains 248 clips representing 0.71 hours of recorded speech (0.19 hours validated) from 14 speakers.

Language

Breton (Brezhoneg) is the only Celtic language spoken on the continent. It belongs to the Brittonic branch of the Celtic languages, like Welsh and Cornish. Breton is classified as "severely endangered" by the UNESCO Atlas of the World's Languages in Danger. The language declined from more than one million speakers around 1950 to less than 200 000 in 2024. After a period of intense protest that began in the 1960s, Breton gradually regained a place in schools, on road signs, then in the media, public life in general, and more recently in digital technology. With the creation of the first bilingual schools at the end of the 1970s, young people were once again speaking Breton, and a change in the way people viewed the language and its use began. Approximately 20 000 pupils attend Breton bilingual classes, either in the Diwan network (immersive teaching) or in bilingual classes in public and catholic school systems. In addition to evening breton classes for adults (~4 000), long-term courses (6 to 9 months) are offered to adults, with approximately 350 places available annually and online courses too (more than 15 000 learners).

Data splits for modelling

The dataset clips are categorised by transcription status and training-set assignment. The following tables summarise the distribution.

Audio clips

Training splits

Training split coverage: 0 of 73 transcribed & validated clips (0.0%)

Transcriptions

The transcription system uses general Latin script, including some diacritics and considering ch and c'h like unique letters. c, q, x may appear in loanwords or foreign language words.

Hesitations in the answers are marked in square brackets (e.g. [euu])

• Prompts: 22

• Duration: 342828[ms]

• Avg. Transcription Len: 92

• Avg. Duration: 12.24[s]

• Valid Duration: 35.03[s]

• Total hours: 0.1[h]

• Valid hours: 0.01[h]

Transcription status

Writing system

The writing system in this dataset uses general Latin script. The diacritics à, è and é may appear in the transcription of Gwenedeg variant.

Symbol table

a â b ch c'h d e ê f g h i j k l m n ñ o ô p r s t u ù û ü v w y z

à è é (for gwenedeg variant)

c q x (foreign, loanwords)

Samples

Questions

There follows a randomly selected sample of questions used in the corpus.

1. Peseurt mare eus ar bloaz a blij deocʼh ha perak ?

2. Daoust ha loened-ti ho peus ?

3. Daoust ha plijout a ra deocʼh enrollañ ho mouezh war CommonVoice ?

4. Peseurt loened a cʼhaller kavout en un ti-feurm ?

5. Penaos e vez fardet krampouezh ?

Responses

There follows a randomly selected sample of transcribed responses from the corpus.

1. Ar wech kentañ eo din en ober, [euu] lâran ket eo plijus met ma servij d'unan bennak [euu] ret eo ober gantañ.

2. Pemp frouezhenn, orañjez, bananenn, avaloù, per, kerez. Pezh a blij din ar muioc'h marteze eo an avaloù.

3. N'am eus ket soñj deus ur gwallhunvre graet ganin nevez zo.

4. Soñj 'm eus eus ur pred mat-tre 'm eus debret : an "tartiflette".

5. Pezh a blij din ar muiañ eo lenn levrioù istorel.

Recommended post-processing

In Breton, c'h is considered to be a letter. To avoid confusion with the final apostrophe (U+2019 RIGHT SINGLE QUOTATION MARK), you can use the character U+02BC MODIFIER LETTER APOSTROPHE for natural language processing purposes.

c'h : U+0063 LATIN SMALL LETTER C U+02BC MODIFIER LETTER APOSTROPHE U+0068 LATIN SMALL LETTER H

Fields

Each row of a tsv file represents a single audio clip, and contains the following information:

• client_id - hashed UUID of a given user

• audio_id - numeric id for audio file

• audio_file - audio file name

• duration_ms - duration of audio in milliseconds

• prompt_id - numeric id for prompt

• prompt - question for user

• transcription - transcription of the audio response

• votes - number of people that who approved a given transcript

• age - age of the speaker1

• gender - gender of the speaker1

• language - language name

• split - for data modelling, which subset of the data does this clip pertain to

• char_per_sec - how many characters of transcription per second of audio

• quality_tags - some automated assessment of the transcription--audio pair, separated by |

  • transcription-length - character per second under 3 characters per second

  • speech-rate - characters per second over 30 characters per second

  • short-audio - audio length under 2 seconds

  • long-audio - audio length over 5 minutes

Get involved

Community links

• Original language request on GitHub

• Ofis Publik ar Brezhoneg (public institution in charge of promoting and developing the teaching and use of the Breton language in everyday life)

• Porched niverel ar brezhoneg (portal gathering various digital tools relating to the Breton language)

• Common Voice translators on Pontoon

• Common Voice Communities

Discussions

• Common Voice on Matrix

• Common Voice on Discourse

• Common Voice on Discord

• Common Voice on Telegram

Contribute

• Contribute questions

• Validate questions

• Answer questions

• Transcribe recordings

• Validate transcriptions

Acknowledgements

Datasheet authors

Contact us via https://www.fr.brezhoneg.bzh/171-contact.htm

Licence

This dataset is released under the Creative Commons Zero (CC-0) licence. By downloading this data you agree to not determine the identity of speakers in the dataset.

Footnotes

1. For a full list of age, gender, and accent options, see the demographics spec. These will only be reported if the speaker opted in to provide that information. ↩ ↩2