— Refund Estimator —
Calculate your IRS penalty refund.
Sixty seconds. No upfront cost. Confidential. We respond within one business day with a refund estimate based on your IRS transcripts.
— Refund Calculator —
See if your business qualifies.
— Specialized Calculators —
Estimate a specific penalty.
Late-Filing Penalty
Failure-to-file: 5% per month, up to 25%.
Open calculator →Failure-to-Pay Penalty
Late payment: 0.5% per month, up to 25%.
Open calculator →Estimated-Tax Safe Harbor
Did you pay enough? 90% / 100% / 110% check.
Open calculator →Interest on Back Taxes
IRS interest, compounded daily.
Open calculator →Abatement Refund Estimator
How much of what you paid you could recover.
Open calculator →2026 Tax Deadlines
Filing, extension & estimated-tax due dates.
Open calculator →