SP2013: Adding commas to text fields

There's a lot of threads about getting rid of commas, but I want more commas.

On the NewItem and EditItem screens, I have some number and currency textboxes. My users are entering values in the millions and often typing the wrong number of zeroes. I know you can accomplish this with some jQuery, but how would I do that on a SharePoint page?

The ViewList screens are fine; SharePoint knows these are number or currency columns and displays them fine -- we only need to show them during editing.