Efficient diagnostics for quantum error correction

Fault-tolerant quantum computing will require accurate estimates of the resource overhead under different error correction strategies, but standard metrics such as gate fidelity and diamond distance have been shown to be poor predictors logical performance. We present a scalable experimental approach based on Pauli reconstruction predict performance concatenated codes. Numerical evidence demonstrates that our method significantly outperforms predictions for various models, even with limited data. illustrate how this assists in selection schemes.