For deep mappings, Stand-alone or Reads Tracks when zoomed out, you may see a grey box with text saying "Too much data for rendering" or "Too much data for rendering. Zoom in to view data" presented on a grey background.

Screenshot 2021-04-23 at 10.12.06.png

The conditions where there is too much data to show in the view are given in more detail further down in this entry.

To view your data in detail, please zoom further in. As the amount of data covered becomes less, you will be able to see the mapping in more detail.

How to use the zoom tools is described in our manual here:


If the main reason to wish to view the mapping zoomed fully out is to get a general idea of coverage across the mapping,  the tool "Create Mapping Graph" tool could be of interest. It can be found in the CLC Genomics Workbench toolbox at: 

Track Tools | Graphs | Create Mapping Graph

Using that tool, one can specify the particular coverage type of interest, for example, maybe it is read coverage, or perhaps just paired read coverage, or unaligned ends coverage, etc. Then a graph of the mapping is made. As it is a graph of the type of coverage specified, it contains much less information than the full reads mapping track. This can be viewed easily when fully zoomed out.

To view one or more mapping graph tracks at once, perhaps with the reads mapping track as well, a track list could be created.

The Create Mapping Graph tool is described in the manual as follows:

If coverage is of interest, another tool that might be of interest is the Coverage Analysis tool, described in the manual here:


Conditions leading to the message "Too much data for rendering"

The message "Too much data for rendering" on top of the grey box appears when:

  • You are working with Reads tracks and there are more than 500,000 reads in the (visible) interval you can see in the Workbench. Paired reads count as 1 read for this limit.

  • You are working with a Stand alone mapping and:

    a) There are more than 200,000 reads in the interval you can see in the Workbench viewing area. Paired reads count as 1 read for this limit.


    b) There region of the reference sequence in the Workbench view is longer than 200,000 bases.

The intervals counted over are 100 base pairs in both directions. To illustrate the meaning of "interval" here, if you set the text size to huge and resized the Workbench window to be very, very thin, so you could only see 10 bases of the reference, then the number of reads being considered will be those over a 210 base region.