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Model Comparison

Claude Sonnet 5.5 vs DeepSeek V4.1 Flash

Claude Sonnet 5.5 (max effort) leads DeepSeek V4.1 Flash (max) by 521 Elo, and their 95% ranges sit 428 Elo apart. Among 78 models, each ranked by its best configuration, Claude Sonnet 5.5 is #2 and DeepSeek V4.1 Flash is #14. Cost per script: $1.38 for Claude Sonnet 5.5 (max effort) and $0.017 for DeepSeek V4.1 Flash (max).

Last updated , from board data generated at 01:13 UTC.

Claude Sonnet 5.5
2561 Writing Elo of Claude Sonnet 5.5 (max effort), its best configuration#2 of 78 models · 84.6/100 Writing Score · $1.38 per script5 configurations on the board
DeepSeek V4.1 Flash
2040 Writing Elo of DeepSeek V4.1 Flash (max), its best configuration#14 of 78 models · 81.0/100 Writing Score · $0.017 per script4 configurations on the board

Picks and Verdict

PickClaude Sonnet 5.5

Claude Sonnet 5.5 (xhigh)

Pick Claude Sonnet 5.5 (xhigh) for the script you'll publish, since at $0.302 it's the cheapest Sonnet setting whose range sits fully above every DeepSeek setting.

PickDeepSeek V4.1 Flash

DeepSeek V4.1 Flash (max)

Pick DeepSeek V4.1 Flash (max) for drafts you plan to rewrite, since the board can't separate it from Sonnet at high and it costs $0.017 a script.

This match-up splits in two at Claude Sonnet 5.5 (xhigh). From there up, Sonnet is well clear: xhigh sits 308 Elo above DeepSeek V4.1 Flash (max), with separate ranges, and max effort adds another 213. On each model's best setting, Sonnet is the #2 model of 78 and DeepSeek the #14 model. Below xhigh, I can't justify paying for Sonnet. Claude Sonnet 5.5 (high) and DeepSeek at max share a Writing Elo of 2040 and a Writing Score of 81.0, and Sonnet costs about 5.4 times as much. At low, DeepSeek is slightly ahead, with overlapping ranges, for roughly an eighth of the price. Sonnet at high writes the stronger hook and carries more substance, while DeepSeek at max lands much closer to the target length and varies less from draft to draft. DeepSeek also scales well, gaining 402 Elo from no thinking to max. I'd run xhigh for a script I care about, at $0.302 and about three minutes. Max effort is a clear step up, but at $1.38 and 14.3 minutes a script I'd keep it for the few videos where that step is worth it.

Disclosure: Claude Sonnet 5.5 comes from the same lab as one of the four judges, Claude Opus 5.5. The other three sit outside its lab, so it is never scored by its own lab alone (how the panel works). The judge analysis measures how much each judge favors its own lab.

How to Read the Writing Score, Writing Elo and 95% Ranges

Writing Score and Writing Elo. The Writing Score (0 to 100) is the weighted average of the nine metric scores: seven from the judges, Length Adherence from code and the Slop Score half from each. The Writing Elo is a rating from pairwise comparisons: on each script, each configuration's average across its drafts is compared with every other configuration's, and gaps within the draft-to-draft variation count as draws. Elo rewards winning often, so the two can put configurations in a different order.

Elo ranges. Each 95% range shows how far a configuration's Elo could move if the drafts had come out slightly differently. It comes from resampling every configuration's recorded draft scores on each reference script and ranking again. Comparing two separate ranges does not test the Elo gap between them: ranges far apart are strong evidence for the order, and overlapping ranges do not mean a tie. The reference scripts stay fixed, so the ranges say nothing about new scripts. The methodology page has the full description.

All Thinking Levels of Both Models

Every ranked configuration of Claude Sonnet 5.5 and DeepSeek V4.1 Flash, scored on the same 10 scripts by the same four judges.

How to Read the Chart
  • Each row is one configuration: the model at one thinking level. The dot is its Writing Elo, a rating from pairwise comparisons of the scores on each script, and the bar is its 95% range: how far that Elo could move if the drafts had come out slightly differently.
  • When two bars overlap, the board cannot order those two configurations. Bars far apart are strong evidence for the order.
  • The table under the chart lists the same configurations in the same order and adds the Writing Score (the 0 to 100 consensus of the judges and code), cost, time and configuration rank (the place among all configurations on the board).
Claude Sonnet 5.5DeepSeek V4.1 Flash
ConfigurationWriting Elo95% RangeWriting ScoreCost / ScriptTime / ScriptReasoning TokensConfiguration Rank
Claude Sonnet 5.5 (max effort)25612504 to 261484.6$1.3814.3 minN/A#3
Claude Sonnet 5.5 (xhigh)23482304 to 238383.2$0.3023.1 minN/A#10
Claude Sonnet 5.5 (high)20401984 to 208781.0$0.0921.0 minN/A#27
DeepSeek V4.1 Flash (max)20401999 to 207681.0$0.0172.4 min22,010#28
DeepSeek V4.1 Flash (high)19711925 to 201080.3$0.0121.1 min13,809#38
DeepSeek V4.1 Flash (low)18561815 to 190679.3$0.00770.7 min6,740#46
Claude Sonnet 5.5 (medium)18561812 to 190079.4$0.0650.6 minN/A#47
Claude Sonnet 5.5 (low)18081771 to 184378.9$0.0610.7 minN/A#50
DeepSeek V4.1 Flash (no thinking)16381588 to 168076.8$0.00370.3 min0#61

Cost is one script at the API list price of the route used, uncached and without judging. Time is the average for one accepted script, retries included. N/A under Reasoning Tokens means the board has no separate reasoning count for that route.

Computed Findings Across Thinking Levels

Each finding is computed from the configurations above. Where two 95% ranges overlap, the board cannot order those two configurations.

Writing Elo at Each Shared Level Name

LevelClaude Sonnet 5.5DeepSeek V4.1 FlashGap95% Ranges
low18081856-48Overlap
high20401971+69Overlap
max25612040+521Separate

Gap is Claude Sonnet 5.5 minus DeepSeek V4.1 Flash at the same level name, using each model's highest-rated configuration at that level.

Two Chosen Configurations Compared

Pick one configuration of each model to compare their metric scores, consistency across drafts and per-script scores. Each menu starts on the model's best configuration.

Scores by Metric

Claude Sonnet 5.5 (max effort)DeepSeek V4.1 Flash (max)Solid bar: higher score in that row

Claude Sonnet 5.5 (max effort) scores higher on all nine metrics. Weighted by each metric's share of the Writing Score, Substance, Accuracy & Value does the most to put Claude Sonnet 5.5 (max effort) ahead, with a 5.3-point lead on that metric. The weight beside each metric is its share of the Writing Score.

Tone & Voice Match19% weight
80.5
78.1
Writing Craft & Clarity13% weight
81.8
78.0
Substance, Accuracy & Value15% weight
87.8
82.5
Continuity & Emotion14% weight
84.5
80.1
YouTube Best Practices12% weight
82.6
79.8
Hook Strength10% weight
81.0
80.1
Length Adherence8% weight
98.8
95.9
Slop Score5% weight
87.8
83.2
Visual Cue Quality4% weight
84.4
76.0

Consistency Across Drafts

Claude Sonnet 5.5 (max effort)DeepSeek V4.1 Flash (max)
Score spread across drafts (±)1.221.30
Lowest script score83.0 Script 1079.7 Script 10
Highest script score86.7 Script 982.4 Script 7
Range across scripts3.72.7

Spread is how much the Writing Score moves between a configuration's drafts, and lower is steadier. Green marks the better number in each row.

Scores by Script

Writing Score on each reference script. Gap is Claude Sonnet 5.5 (max effort) minus DeepSeek V4.1 Flash (max), and the higher score is in bold.

ScriptClaude Sonnet 5.5 (max effort)DeepSeek V4.1 Flash (max)Gap
Script 1 opinion / warning explainer84.280.8+3.4
Script 2 news-analysis / skeptical explainer84.881.2+3.6
Script 3 personal roadmap / opinion84.081.2+2.8
Script 4 short explainer85.080.1+4.9
Script 5 news-analysis / opinion explainer84.881.1+3.7
Script 6 founder announcement / personal origin story84.680.8+3.8
Script 7 personal technical walkthrough / agentic workflow case study85.082.4+2.6
Script 8 product release announcement / personal observation83.980.7+3.2
Script 9 career guide / hiring analysis86.782.2+4.5
Script 10 engineering process walkthrough / presentation adaptation83.079.7+3.3

Compare With Another Model

Pick a second model. A pair with its own written match-up opens that page, and any other pair opens in the comparison tool.

Nearby Match-Ups by Best Writing Elo

Every configuration wrote five drafts for each of the same 10 briefs, from the same prompt. Generation was closed-book, with the prompt as the only source and no web search or other tools. Each judge scores every draft once: Claude Opus 5.5 at medium effort through the Claude Code subscription, GPT-6.1 Sol at medium reasoning through the Codex CLI, GLM 5.3 Flash through OpenRouter, and Jev 1.13, a typed judge from TypeSafe that answers each metric as a multiple-choice question. The channel's finished script is their reference for the voice, and it gets no score on the board itself.

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