> For the complete documentation index, see [llms.txt](https://knowledge.illumina.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://knowledge.illumina.com/instrumentation/nextseq-500-550/instrumentation-nextseq-500-550-faq-list/000002588.md).

# What is the maximum read length supported in one direction on a NextSeq 500/550 run?

The maximum supported read length for NextSeq 500/550 runs is up to 151 reads in one direction. With this, the maximum total read length configuration is 2x151 (paired, 151 bp reads).

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| *For any feedback or questions regarding this article (Illumina Knowledge Article #2588), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000002588%20-%20Instrumentation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


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