README.md

---
license: cc-by-sa-4.0
language:
- pt
pretty_name: PT-BR Wikipedia (cleaned, encyclopedia only)
size_categories:
- 1M<n<10M
task_categories:
- text-generation
tags:
- pt-br
- brazilian-portuguese
- wikipedia
- encyclopedia
- pretraining
configs:
- config_name: default
  data_files:
  - split: train
    path: data/*.parquet
---

# PT-BR Wikipedia (cleaned, encyclopedia only)

Part of the **MagTina350m pretrain corpus release** by [Dataseek](https://dataseek.com.br)
under the Magestic.ai brand. This is one of nine silver-layer datasets that fed
[`dataseek/magtina350m-base`](https://huggingface.co/dataseek/magtina350m-base).

## Summary

1.08 M Brazilian-Portuguese Wikipedia articles, cleaned of wiki-markup, templates, user-talk welcome banners ("Bem-vindo, X!"), VfD voting discussions, eliminação notification templates, JS/CSS gadget pages and talk-page conversations (detected by inline HHhMMmin timestamps). 35 % of the raw silver was discarded as MediaWiki-internal content. Used at ~2 epochs in MagTina350m pretrain.

## Source and collection method

Source: PT-BR Wikipedia dump (mid-2026 snapshot) → mwparserfromhell → template/reference strip → NFKD normalisation → langid='pt' gate (catches mistaken en/es entries) → length floor 200 chars → **v3 cleanup pass (2026-05-12) — see `scripts/release/cleanup_and_export_wiki.py` — that drops welcome banners, VfD ballots, talk-page timestamp signatures, eliminação notification templates and gadget JS/CSS pages**.

**ETL script (in the MagTina1B repository):** [`scripts/etl/recover_wikipt_cleaned.py`](https://huggingface.co/dataseek/magtina350m-base) *(public release of the ETL scripts is on the roadmap; until then the data card below documents the recipe in full).*

## Filters and deduplication

The following filters were applied before this dataset reached its silver
(release-ready) state:

- Strip wiki templates, refs, infoboxes (initial ETL)
- FastText langid='pt'
- v3 cleanup: 22 pattern filters covering welcome banners, talk pages, VfD votes, eliminação notifications, gadget JS/CSS, redirects
- Inline `HHhMMmin de DD de MMM de YYYY` timestamp filter (catches all talk-page conversation content not already covered)
- len(text) ≥ 200 chars (silver gate, preserved through cleanup)

Global URL-normalised deduplication was applied across all web-derived corpora
(`webpages`, `news`, `blogs`) so the same article does not appear twice across
those three datasets.

## Schema

| Column | Type | Description |
|---|---|---|
| `id` | `int32` | Wikipedia page id. |
| `text` | `string` | Cleaned article text (v2 boilerplate-stripped). |
| `n_chars` | `int32` | Character count of `text`. |
| `n_words` | `int32` | Whitespace-split word count of `text`. |

Columns dropped at export (kept private as ETL internals): `_part`

## Size statistics

| Metric | Value |
|---|---:|
| Rows | 1.08 M (1,084,716) |
| Characters | 2.62 B (2,615,639,056) |
| Estimated tokens (PT-BR, chars / 4.5) | 581.25 M |
| Compressed Parquet on disk | ~1.46 GB |

*Sampled at ~2.8 epochs* — the silver corpus has 581.25 M unique tokens, of which 1.601 B were drawn during MagTina350m's single pretrain pass.

**Used in MagTina350m pretrain:** 1.601 B tokens
(9.2 % of MagTina350m's 17.39 B-token pretrain budget).

## How to load

```python
from datasets import load_dataset

ds = load_dataset("dataseek/ptbr-wiki", split="train", streaming=True)
for row in ds.take(5):
    print(row["text"][:200])
```

Streaming is recommended for the larger configs. For the smaller datasets
(`ptbr-dou`, `ptbr-books-publicos`) eager loading is fine.

## Licensing

CC-BY-SA 4.0 — inherited from Wikipedia. Any derivative work that incorporates this dataset must also be licensed CC-BY-SA-compatible.

**Upstream attribution:** Wikimedia Foundation — https://dumps.wikimedia.org/ptwiki/ ; individual contributors retain copyright per CC-BY-SA 4.0.

## Citation

If you use this dataset, please cite both the upstream source and MagTina350m:

```bibtex
@misc{magtina350m_pretrain_2026,
  title  = {MagTina350m pretrain corpus — PT-BR Wikipedia (cleaned, encyclopedia only)},
  author = {Frasson, Ricardo and {Dataseek Team}},
  year   = 2026,
  publisher = {Hugging Face},
  url    = {https://huggingface.co/datasets/dataseek/ptbr-wiki}
}
```

Please also honour the upstream license terms — for CC-BY-derived data,
attribution to the upstream creators is mandatory; for CC-BY-SA, downstream
derivatives must remain CC-BY-SA-compatible.

## Intended use

- Pre-training, continued pre-training, or domain-adapting of Brazilian Portuguese
  language models.
- PT-BR NLP research where statistically representative public-web / academic /
  legal / encyclopedic data is needed.
- Reproducing or improving on the MagTina350m result.

## Known limitations and PII statement

- **Text was NOT PII-scrubbed.** URLs, emails, phone numbers and personal names
  that occurred in the source data may still be present. We strip zero-width
  characters and normalise Unicode but we do not run an NER pass.
- **Crawled data carries upstream biases** of CommonCrawl, Wikipedia, news outlets
  and academic institutions present in the source. We have not audited these.
- **No safety filtering** beyond langid and basic alpha-ratio gates. Hate-speech,
  spam and adult content present in the source remain unless caught incidentally.
- **Provenance preserved at row level.** Every row has either a `url`, `source` or
  `doc_id` column that points back to upstream — this is intentional, so consumers
  can re-license, redact or filter.

## Related releases

- **Model:** [`dataseek/magtina350m-base`](https://huggingface.co/dataseek/magtina350m-base) (354.6 M params, pretrained on this corpus + 8 sibling datasets)
- **Instruct model:** [`dataseek/magtina350m-instruct`](https://huggingface.co/dataseek/magtina350m-instruct)
- **Sibling datasets:** see `dataseek/ptbr-*` for all nine corpora

## License

[cc-by-sa-4.0](https://spdx.org/licenses/cc-by-sa-4.0.html)