Towards AITowards AIToneBench

Model Comparison

GLM-5.3 vs GPT-5.6 Luna

GLM-5.3 (max) leads GPT-5.6 Luna (ultra) by 408 Elo, and their 95% ranges sit 325 Elo apart. Among 78 models, each ranked by its best configuration, GLM-5.3 is #7 and GPT-5.6 Luna is #24. Cost per script: $0.240 for GLM-5.3 (max) and $0.026 for GPT-5.6 Luna (ultra).

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

GLM-5.3
2220 Writing Elo of GLM-5.3 (max), its best configuration#7 of 78 models · 82.4/100 Writing Score · $0.240 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

PickGLM-5.3

GLM-5.3 (max)

Pick GLM-5.3 (max) for a script that sounds like the channel, with a lead of close to eight points on Tone & Voice Match for $0.240.

PickGPT-5.6 Luna

GPT-5.6 Luna (ultra)

Pick GPT-5.6 Luna (ultra) for an accurate first pass at $0.026 a script that you'll rewrite in your own voice.

GPT-5.6 Luna has the substance and lacks the voice, so I'd write with GLM-5.3. GPT-5.6 Luna (ultra) leads GLM-5.3 (max) on substance by 1.6 points, and the two are within half a point on the Slop Score. On Tone & Voice Match it trails by almost eight points, the widest gap between the two best settings, and by five on YouTube Best Practices. The board follows the voice: GLM-5.3 is the #7 model of 78 and Luna the #24 model, each ranked by its best setting. Luna at ultra sits 408 Elo lower with separate 95% ranges, and GLM wins all ten scripts. Luna's thinking levels decide how I'd run it. From medium to ultra it gains 203 Elo and mostly fixes its length, while the price only goes from $0.0065 to $0.026, so I'd never run it at medium. GLM costs $0.240, about nine times Luna at ultra, and takes 6.1 minutes against 3.1. I'd pay that, because tone is the hardest thing to edit back into a draft. When I only need the facts laid out for under three cents, Luna at ultra does that job well.

Disclosure: GLM-5.3 and GPT-5.6 Luna each come from the same lab as one of the judges (GLM 5.3 Flash 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 GLM-5.3 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).
GLM-5.3GPT-5.6 Luna
ConfigurationWriting Elo95% RangeWriting ScoreCost / ScriptTime / ScriptReasoning TokensConfiguration Rank
GLM-5.3 (max)22202183 to 225982.4$0.2406.1 min46,444#15
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

GLM-5.3 (max)GPT-5.6 Luna (ultra)Solid bar: higher score in that row

GLM-5.3 (max) scores higher on seven of the nine metrics and GPT-5.6 Luna (ultra) on two. Weighted by each metric's share of the Writing Score, Tone & Voice Match does the most to put GLM-5.3 (max) ahead, with a 7.8-point lead on that metric. The weight beside each metric is its share of the Writing Score.

Tone & Voice Match19% weight
79.7
71.9
Writing Craft & Clarity13% weight
78.7
74.7
Substance, Accuracy & Value15% weight
83.2
84.8
Continuity & Emotion14% weight
82.1
77.2
YouTube Best Practices12% weight
81.7
76.6
Hook Strength10% weight
83.4
80.6
Length Adherence8% weight
94.3
91.8
Slop Score5% weight
83.4
83.9
Visual Cue Quality4% weight
79.7
78.4

Consistency Across Drafts

GLM-5.3 (max)GPT-5.6 Luna (ultra)
Score spread across drafts (±)1.392.07
Lowest script score80.5 Script 1076.0 Script 7
Highest script score84.1 Script 780.8 Script 9
Range across scripts3.64.8

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 GLM-5.3 (max) minus GPT-5.6 Luna (ultra), and the higher score is in bold.

ScriptGLM-5.3 (max)GPT-5.6 Luna (ultra)Gap
Script 1 opinion / warning explainer82.178.5+3.6
Script 2 news-analysis / skeptical explainer82.580.3+2.2
Script 3 personal roadmap / opinion81.579.7+1.8
Script 4 short explainer81.077.4+3.6
Script 5 news-analysis / opinion explainer82.579.7+2.8
Script 6 founder announcement / personal origin story82.980.6+2.3
Script 7 personal technical walkthrough / agentic workflow case study84.176.0+8.1
Script 8 product release announcement / personal observation82.778.4+4.3
Script 9 career guide / hiring analysis84.080.8+3.2
Script 10 engineering process walkthrough / presentation adaptation80.576.9+3.6

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.

← All comparisons