Genome Taxonomy Database (GTDB) pre-trained classifiers for QIIME 2

This record contains 16S rRNA classifiers for use with QIIME 2 trained on the Genome Taxonomy Database (GTDB), in accordance with their Creative Commons Attribution-ShareAlike 4.0 International License license (accessed 2026-04-06). 

We plan to update this record with new versions as needed to support both new versions of QIIME 2 and the GTDB.  

The classifiers are cryptographically signed. Instructions for verifying the signature can be found here. The public key is included in the record as `rachis-public-key.asc`.

If you use these classifiers in your work, please be sure to cite GTDB (https://doi.org/10.1093/nar/gkab776) in addition to QIIME 2. 

The GTDB citation, and all other relevant citations, is included in all QIIME 2 Results downstream of this classifier. As always, this information can be obtained by calling `qiime tools citations`, or by viewing the Citations tab at QIIME 2 View. We strongly recommend using these tools to get citation-manager-compatible lists of citations that you can reference from your bioinformatics methods text, to ensure you're giving proper credit to all of the contributors to these resources.

For example, to get the relevant citations for a classifier, you can call:

$ qiime tools citations gtdb-r226.0-2026.4.0.dev-classifier.qza