Preliminary benchmark scores for the iPhone 12 Pro and the iPhone 12 Pro Max have shown up on Geekbench with about a 20% speed improvement over the previous generation.
The iPhone 12 uses the A14 processor which boasts a 6-core CPU and 4-core GPU in a 5 nanometer process. Apple gave an inscrutable benchmark during its "High, Speed" event of "50% faster than other smartphone processors."
Scores vary depending on when the benchmark test was run, battery charge, and background operations. Scores will trend lower during initial setup when the iPhone is cataloging a photo library vs a day later on a full charge.
One score for the iPhone 12 Pro showed a 1613 single-core score and a 4076 multi-core score. This compares well to the iPhone 11 Pro at 1343 single-core and 3478 multi-core.