You can always export your contacts, and its very easy.
Find the list you wish to export from, and click the submenu "Export".
Now click the button "Export now", which will automatically begin building your CSV file.
Depending on the size of your list, this can take a few minutes. You can click the refresh icon, or return later to download your export file.
As soon as the export is completed, you can use the "Download" link, and see how many contacts exists in the file.