You can upload multiple (up to 20) eBird checklists into eBird checklist compiler,
and it will return a single Excel spreadsheet containing all of the checklists.
This spreadsheet contains one column of counts for each checklist,
and one column of comments for each checklist.
A compiled spreadsheet is handy for compiling a Christmas Bird Count, or other such group count.
You might also like such a spreadsheet to summarize a trip, or multiple visits to a location, for example.
What you do
Download eBird checklists (by going to My eBird->Manage My Observations->View or edit->Download).
Save the csv files on your computer.
In the “File upload” form above, select each downloaded checklist file, one at a time.
Each time you select a file, a new button for selecting another file is added.
When you've selected your last file, click “Upload”.
You'll be prompted to open or save the generated Excel spreadsheet.
Note: Excel may open in “PROTECTED VIEW”, displaying an “Enable Editing” button.
You will need to click this button if you want to see the row and column sums;
otherwise they are displayed as zeros.
Internet Explorer users only:
It's my experience that if you open the spreadsheet directly from the browser and
click “Enable Editing”, it destroys the contents of the spreadsheet.
If this happens for you, you must save the spreadsheet to disk before opening it.
It's another inexplicable IE weirdness; you get the correct behavior if you use Firefox or Chrome.
The server deletes all uploaded data after returning the Excel file.