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Model Comparison

Claude Opus 5 vs GPT-6 Astra

Claude Opus 5 (max effort) leads GPT-6 Astra (max) by 134 Elo, and their 95% ranges sit 37 Elo apart. Among 78 models, each ranked by its best configuration, Claude Opus 5 is #5 and GPT-6 Astra is #11. Cost per script: $0.736 for Claude Opus 5 (max effort) and $1.15 for GPT-6 Astra (max).

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

Claude Opus 5
2319 Writing Elo of Claude Opus 5 (max effort), its best configuration#5 of 78 models · 83.3/100 Writing Score · $0.736 per script2 configurations on the board
GPT-6 Astra
2185 Writing Elo of GPT-6 Astra (max), its best configuration#11 of 78 models · 82.3/100 Writing Score · $1.15 per script2 configurations on the board

Picks and Verdict

PickClaude Opus 5

Claude Opus 5 (max effort)

Pick Claude Opus 5 (max effort) when the voice matters most, since its range sits clear of Astra's best and at $0.736 it still costs less than GPT-6 Astra (max).

PickGPT-6 Astra

GPT-6 Astra (medium)

Pick GPT-6 Astra (medium) for a fast, fact-heavy first draft at $0.262 in under two minutes, as long as you fix the length yourself.

The price makes this one easy. Both Claude Opus 5 settings cost less than GPT-6 Astra (max), which charges $1.15 a script, and both rate above it. Among 78 models, each ranked by its best setting, Claude Opus 5 is the #5 model and GPT-6 Astra the #11 model. Claude Opus 5 (max effort) leads Astra's best by 134 Elo, with 95% ranges that don't overlap. Claude Opus 5 (high) is still 43 Elo ahead at well under half the price and the wait, though its range overlaps Astra's, so the board can't separate those two. Astra at max does win four metrics: substance by 3.0 points, plus length, slop and visual cues. Opus takes the other five, led by 6.9 points on YouTube Best Practices, and tone, craft and continuity are harder for me to fix in an edit. Astra's best case is the cheap end. GPT-6 Astra (medium), at $0.262, is the cheapest and fastest setting on this page, with more substance than either Opus setting. For anything that has to sound like me, I'd still run Opus at max effort.

Disclosure: Claude Opus 5 and GPT-6 Astra each come from the same lab as one of the judges (Claude Opus 5.5 and GPT-6.1 Sol). Neither is 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 and GPT-6 Astra, 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 5GPT-6 Astra
ConfigurationWriting Elo95% RangeWriting ScoreCost / ScriptTime / ScriptConfiguration Rank
Claude Opus 5 (max effort)23192260 to 236183.3$0.7365.5 min#11
Claude Opus 5 (high)22282180 to 227882.6$0.4723.5 min#13
GPT-6 Astra (max)21852145 to 222382.3$1.159.2 min#21
GPT-6 Astra (medium)20031968 to 203580.7$0.2621.5 min#32

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.

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.

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 (max effort)GPT-6 Astra (max)Solid bar: higher score in that row

Claude Opus 5 (max effort) scores higher on five of the nine metrics and GPT-6 Astra (max) on four. Weighted by each metric's share of the Writing Score, YouTube Best Practices does the most to put Claude Opus 5 (max effort) ahead, with a 6.9-point lead on that metric. The weight beside each metric is its share of the Writing Score.

Tone & Voice Match19% weight
80.8
77.8
Writing Craft & Clarity13% weight
80.5
78.4
Substance, Accuracy & Value15% weight
84.5
87.5
Continuity & Emotion14% weight
83.7
79.9
YouTube Best Practices12% weight
83.5
76.6
Hook Strength10% weight
82.3
82.1
Length Adherence8% weight
92.0
98.3
Slop Score5% weight
85.1
88.6
Visual Cue Quality4% weight
79.8
83.4

Consistency Across Drafts

Claude Opus 5 (max effort)GPT-6 Astra (max)
Score spread across drafts (±)1.101.87
Lowest script score81.9 Script 1080.6 Script 1
Highest script score84.5 Script 785.8 Script 9
Range across scripts2.65.2

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 (max effort) minus GPT-6 Astra (max), and the higher score is in bold.

ScriptClaude Opus 5 (max effort)GPT-6 Astra (max)Gap
Script 1 opinion / warning explainer83.080.6+2.4
Script 2 news-analysis / skeptical explainer83.482.0+1.4
Script 3 personal roadmap / opinion83.284.3-1.1
Script 4 short explainer83.282.7+0.5
Script 5 news-analysis / opinion explainer83.381.3+2.0
Script 6 founder announcement / personal origin story83.483.6-0.2
Script 7 personal technical walkthrough / agentic workflow case study84.581.6+2.9
Script 8 product release announcement / personal observation83.080.6+2.4
Script 9 career guide / hiring analysis83.685.8-2.2
Script 10 engineering process walkthrough / presentation adaptation81.980.7+1.2

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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