Individuals can claim a 33.33% tax credit for all donations over $5 they make to an approved donee organisation (one that has been approved by Inland Revenue).
Not all pages on Givealittle qualify for a Tax Credit, only the ones that are paying to eligible organisations.
If a Givealittle page qualifies for a tax rebate you will see this checkmark and statement on the page:
You will also see a box with the same message on the screen where you enter your donation details:
And on your receipt: