---
language:
- af
- en
- nr
- nso
- st
- ss
- tn
- ts
- ve
- xh
- zu
tags:
- pretraining
- south-african-languages
- multilingual
- mzansitext
- deduplicated
license: apache-2.0
dataset_info:
  features:
  - name: text
    dtype: string
  - name: lang
    dtype: string
  splits:
  - name: validation
    num_bytes: 50448243
    num_examples: 19940
  - name: test
    num_bytes: 50257814
    num_examples: 19784
  - name: train
    num_bytes: 15178461663
    num_examples: 3744654
  download_size: 9577076320
  dataset_size: 15279167720
configs:
- config_name: default
  data_files:
  - split: validation
    path: data/validation-*
  - split: test
    path: data/test-*
  - split: train
    path: data/train-*
---

# MzansiText — deduplicated release

This is a conservatively deduplicated release of [MzansiText](https://huggingface.co/datasets/uctnlp/mzansi-text), a multilingual pretraining corpus for all eleven official South African languages.

Use the original release to reproduce the paper and its trained models. Use this release for new experiments where cross-source duplicate documents should be removed.

## Dataset details

- Splits: 3,744,654 train rows, 19,940 validation rows, and 19,784 test rows
- Total: 3,784,378 rows
- `lang` values: `afr`, `eng`, `nbl`, `nso`, `sot`, `ssw`, `tsn`, `tso`, `ven`, `xho`, `zul`
- Schema: `text` (string), `lang` (string)
- All eleven languages occur in every split.

Validation and test sets are capped at approximately 2M tokens per language to prevent high-resource languages from dominating early stopping.

## Deduplication

Deduplication is performed before deterministic splitting. Each document is normalized with Unicode NFC, whitespace is collapsed and trimmed, and exact duplicates are identified by `(lang, SHA-256(normalized text))`. The language is part of the key so identical text labelled as different languages is retained.

The process removed 197,926 duplicate rows:

| Language label | Rows removed |
|---|---:|
| `afr` | 165,623 |
| `zul` | 19,156 |
| `xho` | 12,910 |
| `tso` | 231 |
| `sot` | 3 |
| `eng` | 1 |
| `nbl` | 1 |
| `nso` | 1 |
| **Total** | **197,926** |

An audit of the combined train, validation, and test splits found no remaining duplicates under this normalization and per-language key.

## Usage

```python
from datasets import load_dataset

dataset = load_dataset("uctnlp/mzansi-text-deduplicated")
print(dataset)
```

## Reproducibility

- Original paper-reproduction dataset: [uctnlp/mzansi-text](https://huggingface.co/datasets/uctnlp/mzansi-text)
- Deduplication implementation and config: [Anri-Lombard/sallm#123](https://github.com/Anri-Lombard/sallm/pull/123)
- Paper: [arXiv:2603.20732](https://arxiv.org/abs/2603.20732)

## Citation

```bibtex
@misc{lombard2026mzansitextmzansilmopencorpus,
      title={MzansiText and MzansiLM: An Open Corpus and Decoder-Only Language Model for South African Languages},
      author={Anri Lombard and Simbarashe Mawere and Temi Aina and Ethan Wolff and Sbonelo Gumede and Elan Novick and Francois Meyer and Jan Buys},
      year={2026},
      eprint={2603.20732},
      archivePrefix={arXiv},
      primaryClass={cs.CL},
      url={https://arxiv.org/abs/2603.20732},
}
```

## License

Apache License 2.0