You have to fill out a tax return. There are many other factors like filing status, and actual amount in W2 box 1. The W2 usually does not match the paychecks. Only the federal withholding in box 2 affects it.
Here is a blank 1040. Fill it out by hand to test and see how it works
https://www.irs.gov/pub/irs-pdf/f1040.pdf
Instructions
https://www.irs.gov/pub/irs-pdf/i1040gi.pdf
Current year EIC and Tax Tables https://www.irs.gov/pub/irs-pdf/i1040tt.pdf
