Add Indexes or Counters

Simply select the files you want to rename and tap the toolbar actions icon, then select "Rename (x)" from the menu.

Select the "Format" tab.

Indexes

Change the Format Mode to "Name and Index".

Use the Custom Format box to replace the current file names with a new one.

Reorder

The 'Reorder' dialog shows the numbering order for all files to be renamed. You can drag the files into a new ordering if you wish.

Counters

Change the Format Mode to "Name and Counter".

The default counter is 5 digits, so: "00001" for example.

If you insert zeroes to the "Start Numbers At" value, this will change the number of leading zeroes.

Use the Custom Format box to replace the current file names with a new one.