13th Gen Core i9-13900K vs 12th Gen Core i5-12400F
Short answer: which is best?
13th Gen Core i9-13900K is 64.4 % stronger than 12th Gen Core i5-12400F. 13th Gen Core i9-13900K ranks #8 of 102 measured processors at WhatFPS (13,199 CPU score over 2 verified runs). 12th Gen Core i5-12400F ranks #50 of 102 measured processors at WhatFPS (8,030 CPU score over 1 verified runs). The numbers are measured in 3 verified WhatFPS runs — not estimated, not self-reported.
Measured comparison
| Metric | 13th Gen Core i9-13900K | 12th Gen Core i5-12400F |
|---|---|---|
| CPU score (the processor's own performance) | 13,199 | 8,030 |
| Best rig (GAMING — whole PC) | 10,782 | 5,740 |
| Integer (MT) | 12.5 Gop/s | 4.8 Gop/s |
| Single-thread (1T) | 0.88 Gop/s | 0.66 Gop/s |
| Draw calls/s (DX11) | 9,342,700 | 10,971,232 |
| Cores / threads | 24 / 32 | 6 / 12 |
| L3 cache | 36 MB | 18 MB |
Fragz' verdict
The 13th Gen Core i9-13900K takes a commanding lead over the 12th Gen Core i5-12400F, with a 64.4% higher CPU score, though both CPUs have a thin sample size of only one or two verified runs. This performance gap is driven by its significantly higher single-thread performance of 0.88 Gop/s compared to 0.66 Gop/s, which often dictates gaming FPS ceilings, alongside a massive jump in multi-threaded integer performance (12.5 Gop/s vs 4.8 Gop/s). The i9-13900K also boasts a much higher core/thread count (24 cores, 32 threads vs 6 cores, 12 threads), more L3 cache (36 MB vs 18 MB), and a higher peak clock of 6119 MHz compared to 4137 MHz, contributing to its overall lead. While the 12th Gen Core i5-12400F showed a higher Supernova DX11 FPS at 91.5 and more draw calls per second, the overall CPU score and single-thread strength of the i9-13900K make it the clear performance leader for demanding gaming and background tasks. For gamers looking for top-tier processing power and future-proofing, the 13th Gen Core i9-13900K is the superior choice, while the 12th Gen Core i5-12400F could still be a solid option for more budget-conscious builds where raw multi-threaded power isn't the absolute priority.
Generated October 31, 2026 from the 3 verified runs available then. The verdict is never silently rewritten — new numbers get a new verdict.
What the numbers mean
The CPU score is the processor's own performance — that is what we rank on. GAMING is the whole rig's score in the best PC we measured the processor in, and leans heavily on the graphics card. A strong processor in a weak PC gets a low GAMING score without being worse. We show both and never mix them.
All numbers come from our benchmark suite: four hand-built 3D scenes written directly against the graphics APIs in Rust, the same load on every PC. The methodology is open at https://whatfps.com/metodik
All measurements for 13th Gen Core i9-13900K · All measurements for 12th Gen Core i5-12400F