When you save an entry/category that is supposed to have its own URL, Craft will assign it a unique URI, based on the section/category group’s URL Format setting.
For example, let’s say you have a section called News, and its “Entries in this section have their own URLs” checkbox is checked, and it has this URL Format:
news/{slug}
When you save a News entry, Craft will assign it a unique URI based on that URL Format. If the entry’s slug is “foo”, then the first URI Craft will try to assign it will be “news/foo”.
However, if that URI is already taken by another entry/category (or some third party element type), Craft will increment the slug and try again:
- news/foo-1
- news/foo-2
- news/foo-3
- etc.
(If incrementing the slug has no effect on the URI – because the URL Format doesn’t actually contain a {slug}
token – then Craft will simply give up and add a validation error to the element.)
Once it has found a URI that is actually unique, it will update the element’s Slug with the incremented version.
So in your case, when you save a category with the slug “australia” and it becomes “australia-6“, that means that you have 6 other elements that had been saved with the slug “australia” before it, with the same URL Format that your current category has, and so “australia-6” was just the first slug Craft could find that resulted in your category having a unique URI.
To find out which elements your category’s URI is conflicting with, you can go to Entries > All Entries, and search for slug:australia
, and click through each of your category groups in the Categories tab, searching for slug:australia
in each of them.