> 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/miseq/instrumentation-miseq-faq-list/000002315.md).

# How many index cycles can be sequenced on MiSeq?

For MiSeq Control Software (MCS) v3.1 and below, there is no limit to index cycles on MiSeq. The recommended range is 6-10 cycles. >10 cycles per index have not been tested by Illumina.

For MCS v4.0 and higher, the maximum index length is 100 cycles.

* For index lengths between 20-100 bp, use manual mode, as Local Run Manager (LRM) v3 limits index read lengths to 20 bp.

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| *For any feedback or questions regarding this article (Illumina Knowledge Article #2315), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000002315%20-%20Instrumentation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


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