# \#classifier **URL:** https://forum.qiime2.org/tag/classifier/265.md [Latest](https://forum.qiime2.org/latest.md) · [Categories](https://forum.qiime2.org/categories.md) · [Tags](https://forum.qiime2.org/tags.md) --- ## [extract-seq-segments: number of reads vs accuracy of reads.](https://forum.qiime2.org/t/extract-seq-segments-number-of-reads-vs-accuracy-of-reads/34293)
**Author:** [@deClare125](https://forum.qiime2.org/u/deClare125)\ **Replies:** 3\ **Last updated:** [August 19, 2026, 7:06pm UTC](https://forum.qiime2.org/t/extract-seq-segments-number-of-reads-vs-accuracy-of-reads/34293 "2026-08-19T19:06:13Z")
Hi Mike, I read this from your post: "But if you are hoping to strictly stay within the bounds of your expected amplicon length, then Id simply do more iterations, at a much higher similarity, say 90% then go up.", and … --- ## [DeepTaxa, a QIIME 2 plugin for 16S taxonomy](https://forum.qiime2.org/t/deeptaxa-a-qiime-2-plugin-for-16s-taxonomy/34228)
**Author:** [@ahmedmoustafa](https://forum.qiime2.org/u/ahmedmoustafa)\ **Replies:** 1\ **Last updated:** [July 2, 2026, 10:46am UTC](https://forum.qiime2.org/t/deeptaxa-a-qiime-2-plugin-for-16s-taxonomy/34228 "2026-07-02T10:46:59Z")
Hi everyone, I want to share a QIIME 2 plugin that we just released for DeepTaxa. Maybe it is useful for your 16S analysis. DeepTaxa is a deep learning model for the taxonomy of 16S rRNA sequences. It predicts all seve… --- ## [Looking for pre-trained SILVA 138 V4 classifier for QIIME2 2024.10](https://forum.qiime2.org/t/looking-for-pre-trained-silva-138-v4-classifier-for-qiime2-2024-10/34190)
**Author:** [@Richa](https://forum.qiime2.org/u/Richa)\ **Replies:** 7\ **Last updated:** [June 16, 2026, 8:56am UTC](https://forum.qiime2.org/t/looking-for-pre-trained-silva-138-v4-classifier-for-qiime2-2024-10/34190 "2026-06-16T08:56:57Z")
Hi everyone, I am working on 16S rRNA gene V4 region analysis using QIIME2 2024.10 on a Windows machine with WSL (16GB RAM). I am looking for a pre-trained SILVA 138 99% OTU classifier for the V4 region with the followi… --- ## [QIIME2-amplicon-2025.7 16S PacBio classification issues/discussion](https://forum.qiime2.org/t/qiime2-amplicon-2025-7-16s-pacbio-classification-issues-discussion/33999)
**Author:** [@ankurnaqib](https://forum.qiime2.org/u/ankurnaqib)\ **Replies:** 6\ **Last updated:** [February 24, 2026, 9:48pm UTC](https://forum.qiime2.org/t/qiime2-amplicon-2025-7-16s-pacbio-classification-issues-discussion/33999 "2026-02-24T21:48:47Z")
Hi, Apologies in advance for the long post. So I recently tried the GTDB226 classifier for the PacBio 16S full-length data. I am using the qiime2-amplicon-2025.7 version. Based on this reference - How to train a GTDB SS… --- ## [F-metric score in naive bayes classification of self-downloaded HROM microbiome database](https://forum.qiime2.org/t/f-metric-score-in-naive-bayes-classification-of-self-downloaded-hrom-microbiome-database/33946)
**Author:** [@jlco](https://forum.qiime2.org/u/jlco)\ **Replies:** 9\ **Last updated:** [February 3, 2026, 4:14pm UTC](https://forum.qiime2.org/t/f-metric-score-in-naive-bayes-classification-of-self-downloaded-hrom-microbiome-database/33946 "2026-02-03T16:14:18Z")
Hey everyone. I got a question regarding the naive bayes classifier based on the self-downloaded HROM microbiome dataset. hrom-classifier-V1V3.qza (1.4 MB) hrom-classifier-V3V4.qza (1.1 MB) I have created these two c… --- ## [Issue with UNITE classifier for ITS1](https://forum.qiime2.org/t/issue-with-unite-classifier-for-its1/33837)
**Author:** [@mhog](https://forum.qiime2.org/u/mhog)\ **Replies:** 1\ **Last updated:** [December 2, 2025, 4:25pm UTC](https://forum.qiime2.org/t/issue-with-unite-classifier-for-its1/33837 "2025-12-02T16:25:54Z")
Hi there, I’m trying to assign taxonomy to my fungal ITS1 data using a pre-trained UNITE classifier. I’m using QIIME 2 version 2025.10 and conda (miniconda). I was having issues running ITSxpress with my paired-end data… --- ## [confidence filtering pre or post classifier?](https://forum.qiime2.org/t/confidence-filtering-pre-or-post-classifier/33737)
**Author:** [@kbmac](https://forum.qiime2.org/u/kbmac)\ **Replies:** 3\ **Last updated:** [October 30, 2025, 8:41pm UTC](https://forum.qiime2.org/t/confidence-filtering-pre-or-post-classifier/33737 "2025-10-30T20:41:11Z")
Hello all! I’m at the point in my pipeline of assigning taxonomy to my sample of ITS sequences and filtering. I used a UNITE classifier generously provided by Colin Brislawn, and subsequently would like to filter the se… --- ## [train a sequence classifier on your own data](https://forum.qiime2.org/t/train-a-sequence-classifier-on-your-own-data/33356)
**Author:** [@chupperts](https://forum.qiime2.org/u/chupperts)\ **Replies:** 2\ **Last updated:** [June 27, 2025, 11:06am UTC](https://forum.qiime2.org/t/train-a-sequence-classifier-on-your-own-data/33356 "2025-06-27T11:06:55Z")
Dear, I’m currently trying to understand the process of building and using a classifier, but I haven’t been able to find clear answers in the tutorials or forums. To make things clearer, I’ll briefly describe our proje… --- ## [Request for Pre-trained UNITE Classifier (ITS1)](https://forum.qiime2.org/t/request-for-pre-trained-unite-classifier-its1/33066)
**Author:** [@mleon](https://forum.qiime2.org/u/mleon)\ **Replies:** 3\ **Last updated:** [April 30, 2025, 7:09pm UTC](https://forum.qiime2.org/t/request-for-pre-trained-unite-classifier-its1/33066 "2025-04-30T19:09:08Z")
Hi everyone, I'm following the ITSxpress tutorial (Q2-ITSxpress: A tutorial on a QIIME 2 plugin to trim ITS sequences) and trying to use the classifier.qza file mentioned there as a pre-trained classifier. However, when… --- ## [ITS, 18S, 23S and 28S new reference databases to use in QIIME2](https://forum.qiime2.org/t/its-18s-23s-and-28s-new-reference-databases-to-use-in-qiime2/33018)
**Author:** [@A\_Munoz](https://forum.qiime2.org/u/A_Munoz)\ **Replies:** 0\ **Last updated:** [April 17, 2025, 1:37pm UTC](https://forum.qiime2.org/t/its-18s-23s-and-28s-new-reference-databases-to-use-in-qiime2/33018 "2025-04-17T13:37:07Z")
MIMt database has grown and now it includes databases for other markers like ITS, 18S, 23S and 28S to the previous 16S already in use. All the databases have two versions, one with only curated sequences from Target Loc… --- ## [SILVA classifier full lenght vs V3V4](https://forum.qiime2.org/t/silva-classifier-full-lenght-vs-v3v4/33009)
**Author:** [@jpmott](https://forum.qiime2.org/u/jpmott)\ **Replies:** 4\ **Last updated:** [April 16, 2025, 11:50am UTC](https://forum.qiime2.org/t/silva-classifier-full-lenght-vs-v3v4/33009 "2025-04-16T11:50:50Z")
Hi all QIIME2 community, I’m having some trouble at the taxonomy assignment step using a trained classifier (new user of Qiime2 approach). I would prefer working with the latest SILVA 138.2 database. I initially used th… --- ## [Training v4v5 classifier for use with legacy 454 Data](https://forum.qiime2.org/t/training-v4v5-classifier-for-use-with-legacy-454-data/31429)
**Author:** [@454Data](https://forum.qiime2.org/u/454Data)\ **Replies:** 1\ **Last updated:** [September 17, 2024, 6:43pm UTC](https://forum.qiime2.org/t/training-v4v5-classifier-for-use-with-legacy-454-data/31429 "2024-09-17T18:43:44Z")
Hiya Q2 Team! :wave: :qiime2: :sunglasses: I've been working with some legacy 454 data we have, following along with the suggestions made in this helpful post, and it has run beautifully! I removed adapters and primers… --- ## [SILVA data trainign problem.](https://forum.qiime2.org/t/silva-data-trainign-problem/31212)
**Author:** [@Ahsan\_Gilman](https://forum.qiime2.org/u/Ahsan_Gilman)\ **Replies:** 2\ **Last updated:** [August 23, 2024, 4:43am UTC](https://forum.qiime2.org/t/silva-data-trainign-problem/31212 "2024-08-23T04:43:01Z")
Hi, I want to train my classifier with Silva 132.2SSU ref NR 99 dataset.i work with 16s RNA.my device can't load this large dataset.can anyone give the trained classifier.qza file? --- ## [Snakemake pipelines for generating taxonomy classifiers](https://forum.qiime2.org/t/snakemake-pipelines-for-generating-taxonomy-classifiers/29340)
**Author:** [@SoilRotifer](https://forum.qiime2.org/u/SoilRotifer)\ **Replies:** 7\ **Last updated:** [July 25, 2024, 6:20pm UTC](https://forum.qiime2.org/t/snakemake-pipelines-for-generating-taxonomy-classifiers/29340 "2024-07-25T18:20:33Z")
I recently started to learn how to construct Snakemake pipelines this past week. There is still much for me to learn, but I was able to successfully put together a Snakefile, that will: download the 16S rRNA reference … --- ## [Combining taxonomy from different classifiers to eliminate unidentified sequences? \[newbie question\]](https://forum.qiime2.org/t/combining-taxonomy-from-different-classifiers-to-eliminate-unidentified-sequences-newbie-question/30024)
**Author:** [@sarsaparella](https://forum.qiime2.org/u/sarsaparella)\ **Replies:** 2\ **Last updated:** [May 2, 2024, 2:00pm UTC](https://forum.qiime2.org/t/combining-taxonomy-from-different-classifiers-to-eliminate-unidentified-sequences-newbie-question/30024 "2024-05-02T14:00:16Z")
Hello! I'm trying to classify my fungal ITS amplicon data :mushroom: :mushroom: :mushroom: I classified dada2 representative sequences with qiime feature-classifier classify-sklearn using colinbrislawn's classifier (un…