---
license: cc-by-nc-4.0
task_categories:
- automatic-speech-recognition
- translation
language:
- mul
tags:
- code-switching
- multilingual
---

# 🌍 CS-FLEURS: A Massively Multilingual and Code-Switched Speech Dataset

[Paper](https://huggingface.co/papers/2509.14161) | [Code (Data Collection Tool)](https://github.com/brianyan918/sentence-recorder/tree/codeswitching)

## 📖 Overview
CS-FLEURS is a new dataset for developing and evaluating code-switched speech recognition and translation systems beyond high-resourced languages.
* 113 unique code-switched language pairs across 52 languages
* 300 hours of speech data, both read and synthetic

## 📊 Dataset Statistics
CS-FLEURS consists of the following subsets:
* Read-Test: 14 X-English pairs, read speech
* XTTS-Train: 16 X-English pairs, generative TTS
* XTTS-Test1: 16 X-English pairs, generative TTS
* XTTS-Test2: 60 {Arabic, Chinese, Hindi, Spanish}-X pairs, generative TTS
* MMS-Test: 45 X-English pairs, concatenative TTS

| Statistic               | Read-Test | XTTS-Train | XTTS-Test1 | XTTS-Test2 | MMS-Test |
|-------------------------|-----------|------------|------------|------------|----------|
| Duration (hours)        | 17        | 128        | 36         | 42         | 56       |
| Tokens (words)          | 128k      | 889k       | 257k       | 300k       | 315k     |
| Matrix Langs            | 14        | 16         | 16         | 4          | 45       |
| Embedded Langs          | 1         | 1          | 1          | 15         | 1        |
| Total CS Pairs          | 14        | 16         | 16         | 60         | 45       |
| Same-Script Pairs       | 7         | 10         | 10         | 10         | 22       |
| Distinct-Script Pairs   | 7         | 6          | 6          | 51         | 23       |

## 🔽 Sample Usage
Clone with [Git LFS](https://git-lfs.com):

```bash
git lfs install
git clone https://huggingface.co/datasets/byan/cs-fleurs
```

Or load directly in 🤗 Datasets:

```python
from datasets import load_dataset

data = load_dataset("byan/cs-fleurs")
```

## 📜 License
This dataset is licensed under CC BY-NC 4.0.

## 🙏 Citation
If you use this dataset, please cite:
```bibtex
@inproceedings{yan2025cs,
  title={CS-FLEURS: A Massively Multilingual and Code-Switched Speech Dataset},
  author={Yan, Brian and Hamed, Injy and Shimizu, Shuichiro and Lodagala, Vasista and Chen, William and Iakovenko, Olga and Talafha, Bashar and Hussein, Amir and Polok, Alexander and Chang, Kalvin and others},
  booktitle={ICASSP 2025 - 2025 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)},
  year={2025},
  url={https://huggingface.co/papers/2509.14161}
}
```