I wanted to see for myself how long it would take various strengths of quantum computers to brute force a single SHA256 hash. I couldn’t find any comprehensive research, so after finding a couple data points from Bitcoin news sources, I extrapolated the rest.

From what I can tell, the strongest quantum computer currently is ~1k qubits. However, there appear to be many, many caveats. Ex. All qubits aren’t made equal. I’m also not a quantum computer expert at all. These calculations could be way off. Corrections welcome.