These calculators publish the model, state every assumption, and say so when the answer is too close to call. Change the inputs and watch the answer move.
Your bracket, the rate your next dollar costs and the rate you really pay are three different numbers. At $100,000 they are 22%, 29.65% and 20.8%.
There is no single crossover salary. Across the assumptions that matter it moves between $53,000 and $228,000 — see where yours lands.
Break-even is 6.7 years at today's rate. At 8% it never arrives inside thirty years. Put your own numbers in.