The largest production quantum computer that exists today - as in, the largest you personally can get access to - has 5,436 qubits: the D-Wave Advantage system.

The largest production quantum computer that exists today - as in, the largest you personally can get access to - has 5,436 qubits: the D-Wave Advantage system. Admittedly, it's not a gate-model machine that can run Shor's Algorithm, but it is a quantum computer, and at more than double the number of qubits plus far higher inter-qubit connectivity than our previous D-Wave 2000Q, it definitely demonstrates tremendous progress. If you have a moment, you can sign up to use it for free at https://cloud.dwavesys.com https://cloud.dwavesys.com - we have an online IDE, Jupyter notebook training material and tons of docs, a community forum, and of course some shiny demos that submit problems to the live QPU if you want to try them out.