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There is one at http://www.teogathalaw.com/IRS-Penalty-Calculator.php
" Disclaimer: This penalty calculator is for entertainment purposes only. Teogatha Law makes no guarantee about the accuracy or correctness of the penalty calculator. These calculations are derived from a beta (test) version of this tax penalty calculator."
Personally have not used it professionally; so no recommendation is implied.
for AcQuest Tax Penalty & Interest Evaluator 2.14 shareware $50 to buy
There is a ten days of use or five uses trial at
A FREE demo from DenverTax, dnt12210.exe (4,476kb), can be downloaded http://www.denvertax.com/int/
As you know, it is not easy to find free software but this is what is available.