Practical overview
When it fits
Use T-NER when an NER workflow needs transformer fine-tuning and evaluation across more than one domain or language, or when adapting a model with custom IOB-formatted annotations.
Who it is for
- Python developers building or adapting named-entity recognition models.
- Researchers comparing NER performance across datasets, domains, or languages.
Documented uses
- Fine-tune a language model for named-entity recognition.
- Evaluate an NER model across domains or languages.
- Use public NER datasets or prepare custom annotated data in IOB format.
- Run the repository's Colab examples for fine-tuning and evaluation, prediction, or multilingual workflows.
Requirements & limits
The library is available through pip and is released under the MIT license.
- Custom datasets need one-word-per-line IOB annotations, blank-line sentence boundaries, and a label-to-index mapping.
- The repository describes public datasets and multi-dataset concatenation with a unified entity-label set.
- The README links to Colab workflows and says fine-tuned models can be deployed to a web app for visualization.
Check current requirements in the official documentation. Source-based guidance does not mean OpenViST has run or independently tested this project.
Format a custom NER dataset for T-NER
Prepare annotated examples in the custom-data format described by the repository.
Before you start
- A custom NER dataset with sentence boundaries and entity labels.
- A label-to-index mapping.
Steps
Write one word per line.
Add an IOB entity tag to each word, using O for words outside entities and B-/I- tags for entity types.
Separate sentences with blank lines.
Prepare a label2id mapping for the tags.
Expected outcome
A custom dataset formatted in the IOB style described for use with T-NER.
Guide limitations
- These steps cover data formatting only, not loading the dataset, fine-tuning a model, or evaluating results.
Sources & review
Source record details
- Source availability
- Active
- Sources checked
- 17 October 2026
- Original website title
- asahi417/tner · Official homepage title · retained in its source language

