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IRS Penalty Calculator

Estimate IRS penalties for late filing, late payment, or underpayment of estimated taxes based on the amount owed and how many days past the deadline you are. Helpful for taxpayers deciding whether to file for an extension or pay immediately.

Tax Amount Owed ($)

Days Late (days)

Penalty Type

Reasonable Cause Expected

Fill in the required fields to see your result.

Taxes

Payroll Tax Calculator

Calculates the combined US federal payroll tax (Social Security plus Medicare, jointly known as FICA) owed on a given block of wages, using the specified employee-side rates. Useful for paycheck planning, comparing self-employment to W-2 take-home, and verifying that an employer has withheld the correct FICA amount.

Wages ($)

Social Security Rate (%)

Medicare Rate (%)

Fill in the required fields to see your result.

Key differences

	IRS Penalty Calculator	Payroll Tax Calculator
Category	Taxes	Taxes
Inputs required	4	3
Result	Total IRS Penalties ($)	Total Payroll Tax ($)
What it does	Estimate IRS penalties for late filing, late payment, or underpayment of estimated taxes based on the amount owed and how many days past the deadline you are. Helpful for taxpayers deciding whether to file for an extension or pay immediately.	Calculates the combined US federal payroll tax (Social Security plus Medicare, jointly known as FICA) owed on a given block of wages, using the specified employee-side rates. Useful for paycheck planning, comparing self-employment to W-2 take-home, and verifying that an employer has withheld the correct FICA amount.