> For the complete documentation index, see [llms.txt](https://help.connected.illumina.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.connected.illumina.com/dragen-single-cell-rna/analysis-results/dragen-report/trimmer.md).

# Trimmer

### Trimmed Reads

| Metric                    | Description                                                                    |
| ------------------------- | ------------------------------------------------------------------------------ |
| Input Reads               | Total number of input reads to DRAGEN                                          |
| Max Read Length           | Maximum detected input read length                                             |
| Average Input Read Length | Average input read length to DRAGEN, after any adapter trimming by BCL Convert |
| Masked                    | Total number 3’ Poly-G bases masked from mapping                               |
| Trimmed                   | Total number of reads trimmed by DRAGEN                                        |
| Filtered                  | Total number of reads removed from the input by DRAGEN                         |

### Trimmer Metrics

| Metric       | Description                                |
| ------------ | ------------------------------------------ |
| Fixed-Length | Total number of fixed-length trimmed reads |
| Adapter      | Total number of adapter trimmed reads      |


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