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Kimi K3 vs Qwen3.8 Max

Should you write with Kimi K3 or Qwen3.8 Max? On this page the only thing that changes is the model. Both wrote their own version of the scripts behind 10 of my What's AI videos, five drafts per script, and three judges from three model families scored every draft blind, with my finished script as the reference. Kimi K3 leads overall, 88.5 to 83.2.

Kimi K3
#21 Elo 2217 · 88.5/100
Qwen3.8 Max
#68 Elo 1682 · 83.2/100
Cost / script
$0.260 vs $0.161
Human baseline
90.9 Kimi K3 falls below it · Qwen3.8 Max falls below it

The verdict

Kimi K3 is the one I'd use. It ranks #21, Qwen3.8 Max #68, and the gap sits in tone and continuity, eight or nine points each. Qwen3.8 Max hits the length target very reliably, a few points better than Kimi, but the judges score it far lower on sounding like someone talking. It doesn't save you much either: about $0.161 a script against $0.260, and it's the slower of the two at around seven minutes. The three judges also disagree more on it, and Kimi is the open-weights one. Qwen3.8 Max only wins when landing exactly on length matters more than the voice.

Pick Kimi K3 when voice and flow matter and you'd like open weights.
Pick Qwen3.8 Max only when exact length is the priority.

How to read these numbers

Overall vs Elo. Overall is the weighted rubric score. Elo compares each model's five-draft average with every other model's, script by script, and counts gaps inside run-to-run noise as draws, so it rewards winning often and can disagree with overall. My own scripts score 90.9 on the same rubric, not a literal 100. Right now 2 of 167 ranked configurations reach it. A model above that line writes at that level on this rubric. That's not the same as beating my script line for line.

Reading the Elo intervals. Each 95% range comes from resampling every model's recorded run scores on each task and re-ranking. Comparing these separate ranges does not test the Elo gap between two models: far apart is strong evidence, and overlap isn't a tie. The tasks stay fixed, so the ranges say nothing about new tasks (the long version).

Metric by metric: where the gap comes from

Blue is Kimi K3, orange is Qwen3.8 Max, and the solid bar takes the metric. The weight under each name is how much it counts toward the overall. Weighted by how much each metric counts, Tone & Voice Match does the most to put Kimi K3 ahead: it leads there by 8.2 points. If you care about one thing, say voice or length, go straight to that row.

Tone & Voice Match19% weight
88.4
80.2
Writing Craft & Clarity13% weight
89.0
82.0
Substance, Accuracy & Value15% weight
87.6
84.4
Continuity & Emotion14% weight
87.6
78.4
YouTube Best Practices12% weight
88.4
82.5
Hook Strength10% weight
89.2
83.0
Length Adherence8% weight
90.1
94.0
Slop Score (EQ-Bench + ours)5% weight
91.2
90.7
Visual Cue Quality4% weight
85.1
84.2

Cost, speed, and consistency

Quality is half the decision. The other half is what each script costs you, how long you wait, and how often you get a bad draft. The lead has a price: Kimi K3 costs about 1.6x as much per script as Qwen3.8 Max.

Kimi K3Qwen3.8 Max
Overall / 10088.583.2
Writing Elo22171682
Score spread across drafts (± overall std)1.2601.980
Cost per script (USD)0.2600.161
Avg time per script (min)3.97.2
Open weightsYesNo

Green wins the row, and for spread, cost and time, lower wins. Cost is one script at recorded list prices, uncached and without judging, so your real bill will differ. Spread is how much the overall score moves across a model's drafts, and time is the average time to get one accepted script, retries included.

Want the script-by-script detail? Full scorecards: Kimi K3 · Qwen3.8 Max. The whole scoring pipeline is on the methodology page.

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