  We present GlotScript, an open resource and tool for low resource writing
system identification. GlotScript-R is a resource that provides the attested
writing systems for more than 7,000 languages. It is compiled by aggregating
information from existing writing system resources. GlotScript-T is a writing
system identification tool that covers all 161 Unicode 15.0 scripts. For an
input text, it returns its script distribution where scripts are identified by
ISO 15924 codes. We also present two use cases for GlotScript. First, we
demonstrate that GlotScript can help cleaning multilingual corpora such as mC4
and OSCAR. Second, we analyze the tokenization of a number of language models
such as GPT-4 using GlotScript and provide insights on the coverage of low
resource scripts and languages by each language model. We hope that GlotScript
will become a useful resource for work on low resource languages in the NLP
community. GlotScript-R and GlotScript-T are available at
https://github.com/cisnlp/GlotScript.
