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Model Comparison

Claude Sonnet 5.5 vs GLM-5.3

Claude Sonnet 5.5 (max effort) leads GLM-5.3 (max) by 341 Elo, and their 95% ranges sit 245 Elo apart. Among 78 models, each ranked by its best configuration, Claude Sonnet 5.5 is #2 and GLM-5.3 is #7. Cost per script: $1.38 for Claude Sonnet 5.5 (max effort) and $0.240 for GLM-5.3 (max).

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

Claude Sonnet 5.5
2561 Writing Elo of Claude Sonnet 5.5 (max effort), its best configuration#2 of 78 models · 84.6/100 Writing Score · $1.38 per script5 configurations on the board
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

Picks and Verdict

PickClaude Sonnet 5.5

Claude Sonnet 5.5 (xhigh)

Pick Claude Sonnet 5.5 (xhigh) for most scripts, since it clears GLM-5.3 with separate ranges in about three minutes for $0.302.

PickGLM-5.3

GLM-5.3 (max)

Pick GLM-5.3 (max) over Sonnet at high or below, since $0.240 a script buys a clearly higher Writing Elo and weights you can host yourself.

Only the top two Claude Sonnet 5.5 settings beat GLM-5.3, so the answer here depends on the setting you run. Claude Sonnet 5.5 (max effort) leads GLM-5.3 (max) by 341 Elo, and their ranges are well apart: the #2 model of 78 against the #7 model. Claude Sonnet 5.5 (xhigh) also clears it, 128 Elo up with separate ranges, at $0.302 a script, about 1.3 times GLM's $0.240, and in about half the time. From high down, every Sonnet setting ranks below GLM, and at high the ranges don't touch. That's how much Sonnet depends on thinking: +753 Elo from low to max effort. Max effort adds another 213 Elo over xhigh, but at about 4.6 times the cost and the wait, so I'd save it for the rare script worth that wait. GLM still writes the better hook, by about two points against both of those Sonnet settings, and its weights are open. And if you run Sonnet at high to save money, GLM-5.3 ranks clearly above it for $0.240 a script against $0.092. Most days, I'd run Sonnet at xhigh.

Disclosure: Claude Sonnet 5.5 and GLM-5.3 each come from the same lab as one of the judges (Claude Opus 5.5 and GLM 5.3 Flash). 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 Sonnet 5.5 and GLM-5.3, 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 Sonnet 5.5GLM-5.3
ConfigurationWriting Elo95% RangeWriting ScoreCost / ScriptTime / ScriptReasoning TokensConfiguration Rank
Claude Sonnet 5.5 (max effort)25612504 to 261484.6$1.3814.3 minN/A#3
Claude Sonnet 5.5 (xhigh)23482304 to 238383.2$0.3023.1 minN/A#10
GLM-5.3 (max)22202183 to 225982.4$0.2406.1 min46,444#15
Claude Sonnet 5.5 (high)20401984 to 208781.0$0.0921.0 minN/A#27
Claude Sonnet 5.5 (medium)18561812 to 190079.4$0.0650.6 minN/A#47
Claude Sonnet 5.5 (low)18081771 to 184378.9$0.0610.7 minN/A#50

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 Sonnet 5.5 (max effort)GLM-5.3 (max)Solid bar: higher score in that row

Claude Sonnet 5.5 (max effort) scores higher on eight of the nine metrics and GLM-5.3 (max) on one. Weighted by each metric's share of the Writing Score, Substance, Accuracy & Value does the most to put Claude Sonnet 5.5 (max effort) ahead, with a 4.6-point lead on that metric. The weight beside each metric is its share of the Writing Score.

Tone & Voice Match19% weight
80.5
79.7
Writing Craft & Clarity13% weight
81.8
78.7
Substance, Accuracy & Value15% weight
87.8
83.2
Continuity & Emotion14% weight
84.5
82.1
YouTube Best Practices12% weight
82.6
81.7
Hook Strength10% weight
81.0
83.4
Length Adherence8% weight
98.8
94.3
Slop Score5% weight
87.8
83.4
Visual Cue Quality4% weight
84.4
79.7

Consistency Across Drafts

Claude Sonnet 5.5 (max effort)GLM-5.3 (max)
Score spread across drafts (±)1.221.39
Lowest script score83.0 Script 1080.5 Script 10
Highest script score86.7 Script 984.1 Script 7
Range across scripts3.73.6

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 Sonnet 5.5 (max effort) minus GLM-5.3 (max), and the higher score is in bold.

ScriptClaude Sonnet 5.5 (max effort)GLM-5.3 (max)Gap
Script 1 opinion / warning explainer84.282.1+2.1
Script 2 news-analysis / skeptical explainer84.882.5+2.3
Script 3 personal roadmap / opinion84.081.5+2.5
Script 4 short explainer85.081.0+4.0
Script 5 news-analysis / opinion explainer84.882.5+2.3
Script 6 founder announcement / personal origin story84.682.9+1.7
Script 7 personal technical walkthrough / agentic workflow case study85.084.1+0.9
Script 8 product release announcement / personal observation83.982.7+1.2
Script 9 career guide / hiring analysis86.784.0+2.7
Script 10 engineering process walkthrough / presentation adaptation83.080.5+2.5

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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