# Filter representative sequences according to sequence's length

**URL:** <https://forum.qiime2.org/t/filter-representative-sequences-according-to-sequences-length/11998>\
**Category:** User Support\
**Tags:** feature-table\
**Created:** [October 16, 2019, 2:23pm UTC](https://forum.qiime2.org/t/filter-representative-sequences-according-to-sequences-length/11998 "2019-10-16T14:23:22Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![yanxianl](https://forum.qiime2.org/user_avatar/forum.qiime2.org/yanxianl/32/2039_2.png) [@yanxianl](https://forum.qiime2.org/u/yanxianl)\
**Post date:** [October 16, 2019, 2:42pm UTC](https://forum.qiime2.org/t/filter-representative-sequences-according-to-sequences-length/11998/2 "2019-10-16T14:42:32Z")

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Hi,

I'm not aware of QIIME2 command lines for filtering sequences based on length. Depending on the primers used, [the amplicon sizes may actually vary quite a bit](https://forum.qiime2.org/t/can-we-use-extracted-reference-reads-to-calculate-expected-amplicon-sizes/11038/3). If the goal is to remove the non-targetted sequences, you can try the [q2-quality-control plugin](https://docs.qiime2.org/2019.7/tutorials/quality-control/), which allows you to filter sequences by alignment, say to a reference database to exclude non-bacterial sequences.

Hope that helps.

-Yanxian

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