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Claude Opus 5 (max) vs DeepSeek V4 Pro 0813 (max)

Should you write with Claude Opus 5 (max) or DeepSeek V4 Pro 0813 (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. Claude Opus 5 (max) leads overall, 89.4 to 84.8. Heads-up: Claude Opus 5 (max) shares its model line with one of the three judges. The panel spans three model families, so no model here is scored by its own family alone (how the panel works).

Claude Opus 5 (max)
#8 Elo 2354 · 89.4/100
DeepSeek V4 Pro 0813 (max)
#56 Elo 1917 · 84.8/100
Cost / script
$0.293 vs $0.021
Human baseline
90.9 Claude Opus 5 (max) falls below it · DeepSeek V4 Pro 0813 (max) falls below it

The verdict

Claude Opus 5 (max effort) is the one I'd use, and the fact that it isn't expensive makes this straightforward. It's #8 against #56 for DeepSeek V4 Pro 0813 (max), and Opus wins every metric, most of all Continuity & Emotion and YouTube Best Practices, by about five to seven points. DeepSeek's case is open weights and about two cents per script against under thirty. That's a real difference if you're generating thousands of scripts, and a small one if you're writing a few a week. For publishing, Opus.

Pick Claude Opus 5 (max effort) for scripts that need to flow and follow YouTube structure, at a modest price.
Pick DeepSeek V4 Pro 0813 (max) for open-weights drafting at scale, where a couple of cents per script matters.

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 Claude Opus 5 (max), orange is DeepSeek V4 Pro 0813 (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, Continuity & Emotion does the most to put Claude Opus 5 (max) ahead: it leads there by 7.2 points. If you care about one thing, say voice or length, go straight to that row.

Tone & Voice Match19% weight
89.6
84.9
Writing Craft & Clarity13% weight
90.4
85.4
Substance, Accuracy & Value15% weight
88.6
84.9
Continuity & Emotion14% weight
89.3
82.1
YouTube Best Practices12% weight
89.8
84.4
Hook Strength10% weight
90.2
86.3
Length Adherence8% weight
88.2
86.1
Slop Score (EQ-Bench + ours)5% weight
91.7
88.3
Visual Cue Quality4% weight
84.8
81.8

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: Claude Opus 5 (max) costs about 14x as much per script as DeepSeek V4 Pro 0813 (max).

Claude Opus 5 (max)DeepSeek V4 Pro 0813 (max)
Overall / 10089.484.8
Writing Elo23541917
Score spread across drafts (± overall std)1.1904.040
Cost per script (USD)0.2930.021
Avg time per script (min)2.23.2
Open weightsNoYes

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: Claude Opus 5 (max) · DeepSeek V4 Pro 0813 (max). The whole scoring pipeline is on the methodology page.

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