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Coref Annotator

This is an annotation tool for coreference. It's built on top of Apache's UIMA, and works with long documents and long coreference chains.


  • Supports annotation of long texts with many discourse entities
  • Mentions can be non-continuous
  • Intuitive drag and drop operations
  • Fully operable by keyboard for fast annotation
  • Annotation texts can be formatted
  • Search function to navigate in long texts
  • Localisable in other languages (currently: English and German)
  • Import and export in a few file formats, including Excel for easy analysis
  • Automatically generated candidates
  • Search terms (including regular expressions) can be annotated en bloc
  • Visualization and some simple quantitative analysis of the annotations

Requirements and Installation

See file

How to cite

If you are using this annotation tool, it would be nice to cite this publication:

Nils Reiter. CorefAnnotator - A New Annotation Tool for Entity References. In Abstracts of EADH: Data in the Digital Humanities, December 2018. DOI: 10.18419/opus-10144

@inproceedings{ Reiter2018ag,
   Title = {{CorefAnnotator - A New Annotation Tool for Entity References}},
   Author = { Nils Reiter },
   Booktitle = {{Abstracts of EADH: Data in the Digital Humanities}},
   Location = { Galway, Ireland },
   Month = { December },
   Doi = { 10.18419/opus-10144 },
   Year = { 2018 }


Main Window

Main Window (v1.0.0-SNAPSHOT)

Annotation Window

Annotation Window (v1.0.0-SNAPSHOT)

Annotation Window with formatted text (v1.9.1)