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Model Comparison

Claude Opus 5.5 vs DeepSeek V4.1 Flash

Claude Opus 5.5 (max effort) leads DeepSeek V4.1 Flash (max) by 748 Elo, and their 95% ranges sit 640 Elo apart. Even Claude Opus 5.5's lowest-rated configuration, Claude Opus 5.5 (low), ranks above DeepSeek V4.1 Flash (max). Among 78 models, each ranked by its best configuration, Claude Opus 5.5 is #1 and DeepSeek V4.1 Flash is #14. Cost per script: $2.58 for Claude Opus 5.5 (max effort) and $0.017 for DeepSeek V4.1 Flash (max).

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

Claude Opus 5.5
2788 Writing Elo of Claude Opus 5.5 (max effort), its best configuration#1 of 78 models · 85.9/100 Writing Score · $2.58 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 Opus 5.5

Claude Opus 5.5 (xhigh)

Pick Claude Opus 5.5 (xhigh) for the script you'll publish, since $1.00 buys the model's top Writing Elo and a lead on all nine metrics.

PickDeepSeek V4.1 Flash

DeepSeek V4.1 Flash (max)

Pick DeepSeek V4.1 Flash (max) for cheap first drafts at $0.017 a script, with the steadiest drafts on this page.

Thinking is almost free on DeepSeek V4.1 Flash, the #14 model of 78, and it pays off. Going from no thinking to max adds 402 Elo while the bill stays under two cents a script. Max and high have overlapping 95% ranges, so the board can't separate those two, and for half a cent more I'd still run max. None of that reaches Claude Opus 5.5, the #1 model. Every Opus setting ranks above every DeepSeek setting: Claude Opus 5.5 (xhigh) sits 748 Elo above DeepSeek V4.1 Flash (max), and even Claude Opus 5.5 (low) leads it by 453, with ranges that don't touch. To be fair to DeepSeek, its max setting is a touch steadier from draft to draft than Opus at xhigh and finishes in 2.4 minutes. Opus at xhigh costs about 59 times as much and leads all nine metrics, by 8.9 points on Visual Cue Quality and about six on substance. I'd pay that dollar for a script I'll publish and no more, because max effort costs $2.58 and its range overlaps xhigh's. First drafts I plan to rework can go to DeepSeek at max.

Disclosure: Claude Opus 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 Opus 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 Opus 5.5DeepSeek V4.1 Flash
ConfigurationWriting Elo95% RangeWriting ScoreCost / ScriptTime / ScriptReasoning TokensConfiguration Rank
Claude Opus 5.5 (max effort)27882716 to 284585.9$2.5817.5 minN/A#1
Claude Opus 5.5 (xhigh)27882727 to 285185.8$1.006.7 minN/A#2
Claude Opus 5.5 (high)25362486 to 257384.6$0.3282.1 minN/A#5
Claude Opus 5.5 (medium)25202469 to 257684.5$0.3101.9 minN/A#6
Claude Opus 5.5 (low)24932436 to 253684.3$0.2431.5 minN/A#7
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
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 Opus 5.5DeepSeek V4.1 FlashGap95% Ranges
low24931856+637Separate
high25361971+565Separate
max27882040+748Separate

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

Claude Opus 5.5 (max effort) scores higher on all nine metrics. Weighted by each metric's share of the Writing Score, Tone & Voice Match does the most to put Claude Opus 5.5 (max effort) ahead, with a 4.7-point lead on that metric. The weight beside each metric is its share of the Writing Score.

Tone & Voice Match19% weight
82.8
78.1
Writing Craft & Clarity13% weight
82.9
78.0
Substance, Accuracy & Value15% weight
88.0
82.5
Continuity & Emotion14% weight
85.7
80.1
YouTube Best Practices12% weight
84.3
79.8
Hook Strength10% weight
83.7
80.1
Length Adherence8% weight
98.7
95.9
Slop Score5% weight
88.4
83.2
Visual Cue Quality4% weight
85.9
76.0

Consistency Across Drafts

Claude Opus 5.5 (max effort)DeepSeek V4.1 Flash (max)
Score spread across drafts (±)1.441.30
Lowest script score83.6 Script 1079.7 Script 10
Highest script score87.3 Script 782.4 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 Opus 5.5 (max effort) minus DeepSeek V4.1 Flash (max), and the higher score is in bold.

ScriptClaude Opus 5.5 (max effort)DeepSeek V4.1 Flash (max)Gap
Script 1 opinion / warning explainer84.680.8+3.8
Script 2 news-analysis / skeptical explainer85.381.2+4.1
Script 3 personal roadmap / opinion86.581.2+5.3
Script 4 short explainer87.080.1+6.9
Script 5 news-analysis / opinion explainer85.981.1+4.8
Script 6 founder announcement / personal origin story86.380.8+5.5
Script 7 personal technical walkthrough / agentic workflow case study87.382.4+4.9
Script 8 product release announcement / personal observation85.580.7+4.8
Script 9 career guide / hiring analysis87.382.2+5.1
Script 10 engineering process walkthrough / presentation adaptation83.679.7+3.9

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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