There’s so many people asking if they need to report their online income on their income taxes that I thought linking to this IRS app that will help you determine if you need to file (or if you should because of a benefit to you even though you don’t have to) might be useful.
This should still give you a good idea if you need to file–click the Begin link below the paragraph of text:
There are other questionnaires like this on the IRS site too (page down below the intro text for links):
If you need to file, you’ll need to report all your income. The following posts should be helpful to you:
Help for Filing your Federal Income Taxes for Your Small Business