You can simulate a Shor’s algorithm factoring 15. You can compile a Grover’s search for a specific backend. You can train a quantum neural network to classify iris species. All without a credit card.
pip install qiskit pennylane pytket stim Then open a Jupyter notebook and build your first circuit. The only thing you have to lose is the assumption that quantum is out of reach. free open source quantum services
With open source, the answer is always: Look at the source. You can simulate a Shor’s algorithm factoring 15
Proprietary quantum clouds are "black boxes." When your simulation fails, is it your code, or a bug in the closed-source simulator? When you pay per shot on a real device, can you verify the result wasn't corrupted by a known bug? is it your code