Towards AITowards AIToneBench

Model Comparison

Claude Fable 5.1 vs Grok 4.7

Claude Fable 5.1 (max effort) leads Grok 4.7 (medium) by 629 Elo, and their 95% ranges sit 539 Elo apart. Even Claude Fable 5.1's lowest-rated configuration, Claude Fable 5.1 (high), ranks above Grok 4.7 (medium). Among 78 models, each ranked by its best configuration, Claude Fable 5.1 is #3 and Grok 4.7 is #22. Cost per script: $3.56 for Claude Fable 5.1 (max effort) and $0.215 for Grok 4.7 (medium).

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

Claude Fable 5.1
2553 Writing Elo of Claude Fable 5.1 (max effort), its best configuration#3 of 78 models · 84.5/100 Writing Score · $3.56 per script2 configurations on the board
Grok 4.7
1924 Writing Elo of Grok 4.7 (medium), its best configuration#22 of 78 models · 79.6/100 Writing Score · $0.215 per script3 configurations on the board

Picks and Verdict

PickClaude Fable 5.1

Claude Fable 5.1 (max effort)

Pick Claude Fable 5.1 (max effort) for the script you film, because it's the best setting of the #3 model of 78, with steadier drafts than the high setting, at $3.56 a script.

PickGrok 4.7

Grok 4.7 (low)

Pick Grok 4.7 (low) for a content draft you'll rewrite anyway, since its substance is within a point of high at $0.064 a script and what you give up is mostly length control.

More thinking mostly buys Grok 4.7 length control. Length Adherence climbs from 68.8 at low to 79.1 at high and substance moves less than a point, for nearly five times the cost. Medium rates just above high, with overlapping 95% ranges, so the board cannot separate them, and high costs more. Fable's extra thinking spreads wider: Claude Fable 5.1 (max effort) sits 201 Elo above Claude Fable 5.1 (high) with separate ranges and scores higher on all nine metrics, for nearly twice the price. Against each other, it isn't close. Claude Fable 5.1 is the #3 model of 78 and Grok 4.7 the #22 model, 629 Elo apart at their best, and both Fable settings rate above all three Grok settings with ranges that never touch. Grok deserves credit for content. At medium it edges Fable's best on Substance, Accuracy & Value by two tenths of a point. The sentences are the problem, with Writing Craft & Clarity 8.9 points behind. So Grok 4.7 (low), at $0.064 and under two minutes, works for me as a content draft I'd rewrite. Fable at max effort writes the script I'd film.

Disclosure: Claude Fable 5.1 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 Fable 5.1 and Grok 4.7, 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 Fable 5.1Grok 4.7
ConfigurationWriting Elo95% RangeWriting ScoreCost / ScriptTime / ScriptReasoning TokensConfiguration Rank
Claude Fable 5.1 (max effort)25532513 to 258784.5$3.5612.3 minN/A#4
Claude Fable 5.1 (high)23522302 to 240383.4$1.856.3 minN/A#9
Grok 4.7 (medium)19241863 to 197479.6$0.2156.2 min27,687#42
Grok 4.7 (high)18971850 to 193979.6$0.3059.6 min42,549#43
Grok 4.7 (low)18341784 to 189079.0$0.0641.7 min2,760#48

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.

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 Fable 5.1 (max effort)Grok 4.7 (medium)Solid bar: higher score in that row

Claude Fable 5.1 (max effort) scores higher on eight of the nine metrics and Grok 4.7 (medium) on one. Weighted by each metric's share of the Writing Score, Length Adherence does the most to put Claude Fable 5.1 (max effort) ahead, with a 19.6-point lead on that metric. The weight beside each metric is its share of the Writing Score.

Tone & Voice Match19% weight
81.8
78.4
Writing Craft & Clarity13% weight
80.8
71.9
Substance, Accuracy & Value15% weight
86.0
86.2
Continuity & Emotion14% weight
84.5
80.0
YouTube Best Practices12% weight
83.7
80.5
Hook Strength10% weight
82.0
81.0
Length Adherence8% weight
98.3
78.7
Slop Score5% weight
86.8
80.5
Visual Cue Quality4% weight
82.7
78.8

Consistency Across Drafts

Claude Fable 5.1 (max effort)Grok 4.7 (medium)
Score spread across drafts (±)1.133.00
Lowest script score82.8 Script 1075.6 Script 10
Highest script score86.2 Script 982.2 Script 2
Range across scripts3.46.6

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 Claude Fable 5.1 (max effort) minus Grok 4.7 (medium), and the higher score is in bold.

ScriptClaude Fable 5.1 (max effort)Grok 4.7 (medium)Gap
Script 1 opinion / warning explainer83.381.5+1.8
Script 2 news-analysis / skeptical explainer83.882.2+1.6
Script 3 personal roadmap / opinion84.081.6+2.4
Script 4 short explainer85.276.9+8.3
Script 5 news-analysis / opinion explainer84.980.5+4.4
Script 6 founder announcement / personal origin story85.082.0+3.0
Script 7 personal technical walkthrough / agentic workflow case study85.376.5+8.8
Script 8 product release announcement / personal observation84.779.0+5.7
Script 9 career guide / hiring analysis86.280.2+6.0
Script 10 engineering process walkthrough / presentation adaptation82.875.6+7.2

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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