How early can you test?

Hi all, Am about halfway through the 2WW (AF due this day next week) but am soooooo tempted to test but don't want to waste the money!! Anyone have any ideas how early you can test? Thanks!

I think First Response will give you an accurate result up to four days before your period is due. Good luck!

if you still have another week togo it would be a waste of money and you will feel disappointed! if you ca hold out to one or two days before!