The gap changes with resolution.
CPU differences shrink as resolution rises — at 4K the graphics card does most of the work.
| Resolution | i5-12400F | i3-13100F | Difference |
|---|---|---|---|
| 1080p | 77 | 75 | +3% |
| 1440p | 74 | 71 | +4% |
| 4K | 71 | 67 | +6% |
In a real build with a RTX 3080.
Specs alone don’t tell you which to buy. Here is what each one does when it’s actually paired up, at 1440p.
| Game (1440p, paired with the RTX 3080) | i5-12400F | i3-13100F |
|---|---|---|
| League of Legends | 300 fps | 295 fps |
| Counter-Strike 2 | 257 fps | 253 fps |
| Grand Theft Auto V | 129 fps | 127 fps |
| Elden Ring | 106 fps | 105 fps |
| Cyberpunk 2077 | 81 fps | 80 fps |
| Starfield | 80 fps | 79 fps |
Modelled from benchmark data, not measured for every pairing. Our published error rate is 21.6% mean absolute error.
So which should you buy?
The i5-12400F is faster, but the i3-13100F is the better buy per dollar. Take the i5-12400F only if you want the extra headroom and the price gap doesn't bother you.
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Common questions.
Straight answers on the i5-12400F versus the i3-13100F.
Is the i5-12400F better than the i3-13100F?
Yes, but by less than the spec sheet suggests. At 1440p the i5-12400F scores 74 against 71 for the i3-13100F — roughly 4% faster. It also costs about $65 more at MSRP, so the question is whether that gap is worth the money for your build.
Does the i5-12400F or i3-13100F bottleneck a RTX 3080?
Paired with a RTX 3080 at 1440p, the i5-12400F build comes out balanced, and the i3-13100F build comes out balanced. Being GPU-bound is the healthy outcome — it means the graphics card is the part working hardest.
Is it worth upgrading from the i3-13100F to the i5-12400F?
Only if you are also lifting the rest of the build. The i5-12400F is about 4% ahead at 1440p, and gaps like that shrink further at 4K where the GPU does more of the work. If you are upgrading from the i3-13100F purely for frames, check the pairing first.
Which is better value, the i5-12400F or the i3-13100F?
On performance per dollar at MSRP, the i3-13100F wins. The i5-12400F lists at $174 for an index of 74, and the i3-13100F at $109 for 71.
Check either one against your build.
Pick a CPU and its counterpart, and get a verdict at all three resolutions in under 30 seconds.