I just had a child on July 2019 and would like to know if I should claim 7 allowances on my w4 form? I used the worksheet provided in the w4 to determine the number.

[peterthecheat]

1 for "myself"
> 1 for "head of household"
> 1 for "single and with only one job"
> 4 for "child tax credit with under $71,000 in income" (says to put 4 for each child.

[bluedeb]

The W-4 is an IRS form you complete to let your employer know how much money to withhold from your paycheck for federal taxes. The less taxes (more allowances) you have taken out of each paycheck gives you more money in the paycheck each week.  The more taxes you have taken out (less allowances) the less money you bring home each week, but might get you a bigger refund at income tax time.

Since you are the only one working the amount of allowances from the W4 worksheet should be OK.  

You can also check out the IRS W4 Estimator

https://www.irs.gov/individuals/tax-withholding-estimator