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Model Comparison

DeepSeek V4.1 Flash vs Claude Opus 4.8

Too close to call: the best configurations, DeepSeek V4.1 Flash (max) and Claude Opus 4.8 (max effort), are 27 Elo apart, and their 95% ranges overlap. Among 78 models, each ranked by its best configuration, DeepSeek V4.1 Flash is #14 and Claude Opus 4.8 is #15. Cost per script: $0.017 for DeepSeek V4.1 Flash (max) and $1.23 for Claude Opus 4.8 (max effort).

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

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
Claude Opus 4.8
2013 Writing Elo of Claude Opus 4.8 (max effort), its best configuration#15 of 78 models · 80.7/100 Writing Score · $1.23 per script2 configurations on the board

Picks and Verdict

PickDeepSeek V4.1 Flash

DeepSeek V4.1 Flash (max)

Pick DeepSeek V4.1 Flash (max) for almost every script, since the board can't separate it from Claude Opus 4.8's best and it costs $0.017 a script.

PickClaude Opus 4.8

Claude Opus 4.8 (max effort)

Pick Claude Opus 4.8 (max effort) when cue-heavy scripts are your main format, since its 79.7 on Visual Cue Quality leads every DeepSeek setting.

Price settles this one, because the board can't. DeepSeek V4.1 Flash is #14 of 78 models and Claude Opus 4.8 the #15 model, each ranked by its best setting, and those settings, DeepSeek V4.1 Flash (max) and Claude Opus 4.8 (max effort), sit 27 Elo apart with overlapping 95% ranges. The bills are nowhere near each other: $0.017 a script against $1.23, about 72 times as much, and the Opus draft takes about four times as long. Going down a level doesn't help Opus. At high, the other level name they share, DeepSeek leads by 103 Elo with separate ranges. DeepSeek V4.1 Flash (high), at about a cent, has a range that overlaps the best Opus setting, and DeepSeek V4.1 Flash (low), under a cent, overlaps Claude Opus 4.8 (high). Opus does write the better visual cues, by almost four points at the top settings, so cue-heavy scripts are a fair reason to pay for it. The one DeepSeek setting I'd avoid is no thinking, which sits 402 Elo under max. For me this is DeepSeek at max, and the money saved covers an editing pass on the cues.

Disclosure: Claude Opus 4.8 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 DeepSeek V4.1 Flash and Claude Opus 4.8, 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).
DeepSeek V4.1 FlashClaude Opus 4.8
ConfigurationWriting Elo95% RangeWriting ScoreCost / ScriptTime / ScriptReasoning TokensConfiguration Rank
DeepSeek V4.1 Flash (max)20401999 to 207681.0$0.0172.4 min22,010#28
Claude Opus 4.8 (max effort)20131977 to 204780.7$1.239.8 minN/A#30
DeepSeek V4.1 Flash (high)19711925 to 201080.3$0.0121.1 min13,809#38
Claude Opus 4.8 (high)18681827 to 190579.3$0.1931.4 minN/A#44
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

LevelDeepSeek V4.1 FlashClaude Opus 4.8Gap95% Ranges
high19711868+103Separate
max20402013+27Overlap

Gap is DeepSeek V4.1 Flash minus Claude Opus 4.8 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

DeepSeek V4.1 Flash (max)Claude Opus 4.8 (max effort)Solid bar: higher score in that row

DeepSeek V4.1 Flash (max) scores higher on five of the nine metrics and Claude Opus 4.8 (max effort) on four. Weighted by each metric's share of the Writing Score, Tone & Voice Match does the most to put DeepSeek V4.1 Flash (max) ahead, with a 1.4-point lead on that metric. The weight beside each metric is its share of the Writing Score.

Tone & Voice Match19% weight
78.1
76.7
Writing Craft & Clarity13% weight
78.0
76.7
Substance, Accuracy & Value15% weight
82.5
82.0
Continuity & Emotion14% weight
80.1
80.9
YouTube Best Practices12% weight
79.8
80.4
Hook Strength10% weight
80.1
80.3
Length Adherence8% weight
95.9
94.6
Slop Score5% weight
83.2
82.1
Visual Cue Quality4% weight
76.0
79.7

Consistency Across Drafts

DeepSeek V4.1 Flash (max)Claude Opus 4.8 (max effort)
Score spread across drafts (±)1.302.02
Lowest script score79.7 Script 1077.5 Script 4
Highest script score82.4 Script 783.1 Script 6
Range across scripts2.75.6

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 DeepSeek V4.1 Flash (max) minus Claude Opus 4.8 (max effort), and the higher score is in bold.

ScriptDeepSeek V4.1 Flash (max)Claude Opus 4.8 (max effort)Gap
Script 1 opinion / warning explainer80.880.2+0.6
Script 2 news-analysis / skeptical explainer81.280.6+0.6
Script 3 personal roadmap / opinion81.279.3+1.9
Script 4 short explainer80.177.5+2.6
Script 5 news-analysis / opinion explainer81.180.3+0.8
Script 6 founder announcement / personal origin story80.883.1-2.3
Script 7 personal technical walkthrough / agentic workflow case study82.482.5-0.1
Script 8 product release announcement / personal observation80.782.5-1.8
Script 9 career guide / hiring analysis82.282.0+0.2
Script 10 engineering process walkthrough / presentation adaptation79.778.9+0.8

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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