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Model Comparison

Grok 4.6 vs GPT-5.6 Luna

Grok 4.6 (high) leads GPT-5.6 Luna (ultra) by 166 Elo, and their 95% ranges sit 72 Elo apart. Among 78 models, each ranked by its best configuration, Grok 4.6 is #19 and GPT-5.6 Luna is #24. Cost per script: $0.156 for Grok 4.6 (high) and $0.026 for GPT-5.6 Luna (ultra).

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

Grok 4.6
1978 Writing Elo of Grok 4.6 (high), its best configuration#19 of 78 models · 80.3/100 Writing Score · $0.156 per script1 configuration on the board
GPT-5.6 Luna
1812 Writing Elo of GPT-5.6 Luna (ultra), its best configuration#24 of 78 models · 78.8/100 Writing Score · $0.026 per script2 configurations on the board

Picks and Verdict

PickGrok 4.6

Grok 4.6 (high)

Pick Grok 4.6 (high) when the voice has to come from the model, at $0.156 a script for a lead of almost seven points on tone.

PickGPT-5.6 Luna

GPT-5.6 Luna (ultra)

Pick GPT-5.6 Luna (ultra) for cheap first drafts with a strong hook, at $0.026 a script.

Grok 4.6 (high) is the better writer on this page, and GPT-5.6 Luna (ultra) is the much cheaper one. By best setting, Grok 4.6 is the #19 model of 78 and GPT-5.6 Luna the #24 model. Grok is 166 Elo ahead, and the 95% ranges don't overlap, so the evidence for that order is strong. Most of the gap is voice. Grok is almost seven points ahead on tone and more than three on YouTube structure. Luna's hook is a little stronger and its drafts carry less filler. It also costs $0.026 a script against $0.156 and finishes about two minutes sooner. Luna has a second setting on the board, and I'd avoid it. GPT-5.6 Luna (medium) falls 203 Elo below ultra, and it misses the requested length badly. Ultra fixes that for under three cents. Grok costs about six times as much, which comes to thirteen cents more a script. For a script I'm going to record, I'd pay it. For a cheap first pass that I'll rewrite in my own voice anyway, I'd run Luna at ultra.

Disclosure: GPT-5.6 Luna comes from the same lab as one of the four judges, GPT-6.1 Sol. 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 Grok 4.6 and GPT-5.6 Luna, 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).
Grok 4.6GPT-5.6 Luna
ConfigurationWriting Elo95% RangeWriting ScoreCost / ScriptTime / ScriptReasoning TokensConfiguration Rank
Grok 4.6 (high)19781930 to 202380.3$0.1565.2 min18,588#36
GPT-5.6 Luna (ultra)18121768 to 185878.8$0.0263.1 minN/A#49
GPT-5.6 Luna (medium)16091572 to 164776.7$0.00650.5 minN/A#66

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

Grok 4.6 (high)GPT-5.6 Luna (ultra)Solid bar: higher score in that row

Grok 4.6 (high) scores higher on four of the nine metrics and GPT-5.6 Luna (ultra) on five. Weighted by each metric's share of the Writing Score, Tone & Voice Match does the most to put Grok 4.6 (high) 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
78.8
71.9
Writing Craft & Clarity13% weight
74.0
74.7
Substance, Accuracy & Value15% weight
85.0
84.8
Continuity & Emotion14% weight
79.0
77.2
YouTube Best Practices12% weight
79.9
76.6
Hook Strength10% weight
79.3
80.6
Length Adherence8% weight
90.7
91.8
Slop Score5% weight
80.9
83.9
Visual Cue Quality4% weight
77.1
78.4

Consistency Across Drafts

Grok 4.6 (high)GPT-5.6 Luna (ultra)
Score spread across drafts (±)1.822.07
Lowest script score78.5 Script 376.0 Script 7
Highest script score82.8 Script 680.8 Script 9
Range across scripts4.34.8

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 Grok 4.6 (high) minus GPT-5.6 Luna (ultra), and the higher score is in bold.

ScriptGrok 4.6 (high)GPT-5.6 Luna (ultra)Gap
Script 1 opinion / warning explainer81.678.5+3.1
Script 2 news-analysis / skeptical explainer80.880.3+0.5
Script 3 personal roadmap / opinion78.579.7-1.2
Script 4 short explainer80.277.4+2.8
Script 5 news-analysis / opinion explainer81.179.7+1.4
Script 6 founder announcement / personal origin story82.880.6+2.2
Script 7 personal technical walkthrough / agentic workflow case study79.076.0+3.0
Script 8 product release announcement / personal observation79.778.4+1.3
Script 9 career guide / hiring analysis80.480.8-0.4
Script 10 engineering process walkthrough / presentation adaptation79.176.9+2.2

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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