Code: Megapixel99/countfn Every empirical complexity tool I could find on either registry measures elapsed time. PyPI's big-O estimates the class from execution time, and npm's big-o-calculator times growing inputs and reports the "probable" complexity; neither can refuse to answer. countfn counts operations instead: hand it a function, a ladder of input sizes, and a builder for the inputs, and it reports how each kind of work grows, or refuses. pip install countfn ...