When filing for exemptions, the expectation is that you will use the formula so that your taxes are taken at the rate you are supposed to pay.
I.E. If you claim 10 dependents, the taxes withheld will be what the formula says needs to be taken out. The more exemptions, the less tax.
Link to their calculator:
https://apps.irs.gov/app/withholdingcalculator/
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