On raw benchmark numbers, the Xiaomi 15T pulls decisively ahead. Its AnTuTu score of 1,821,100 is roughly 70% higher than the Pixel 9a's 1,071,616, and its Geekbench 6 multi-core result of 6,033 outpaces the Pixel 9a's 4,500 by a substantial margin. This reflects the Dimensity 8400's faster clock speeds across all core clusters — every tier of the 15T's CPU runs at a higher frequency. In day-to-day use, this gap is most felt during sustained workloads like video editing, gaming, or heavy multitasking. One notable counterpoint: single-core performance is essentially identical (1,571 vs 1,600 in favor of the Pixel 9a), meaning routine single-threaded tasks like launching apps or scrolling feel comparably snappy on both.
The GPU story also favors the 15T, with a GPU clock speed of 1,300 MHz versus the Pixel 9a's 940 MHz — a 38% advantage that directly translates to smoother frame rates in graphically demanding games. Complementing this, the 15T ships with 12 GB of RAM and 512 GB of storage compared to the Pixel 9a's 8 GB and 256 GB, giving it more headroom for background app retention and media storage. One area where the Pixel 9a holds a structural edge is its 8 MB L2 cache versus the 15T's 1 MB — larger L2 cache can reduce latency for frequently accessed data — though the 15T compensates with a larger 6 MB L3 cache.
The Xiaomi 15T is the clear performance winner in this group. The Pixel 9a holds its own in single-core tasks, but the 15T's advantages in multi-core throughput, GPU power, RAM, and storage capacity make it the stronger choice for users who push their devices hard.