W-4 Extra Withholding Calculator (Line 4(c))
Estimate your annual tax shortfall from equity (expected tax minus expected withholding), then spread it across remaining paychecks.
Inputs
e.g. 12 monthly, 26 biweekly, 24 semi-monthly
Enter positive numbers.
Guides: W-4 adjustments, estimated tax.
Related guides
Go deeper on the rules and planning ideas behind this calculator.