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Model Comparison

Kimi K3.1 Pro vs GLM-5.3 Flash

Kimi K3.1 Pro (max) leads GLM-5.3 Flash (max) by 92 Elo, and their 95% ranges sit 13 Elo apart. Among 83 models, each ranked by its best configuration, Kimi K3.1 Pro is #7 and GLM-5.3 Flash is #13. Cost per script: $0.251 for Kimi K3.1 Pro (max) and $0.022 for GLM-5.3 Flash (max).

Last updated , from board data generated at 22:06 UTC.

Kimi K3.1 Pro
2205 Writing Elo of Kimi K3.1 Pro (max), its best configuration#7 of 83 models · 82.5/100 Writing Score · $0.251 per script1 configuration on the board
GLM-5.3 Flash
2113 Writing Elo of GLM-5.3 Flash (max), its best configuration#13 of 83 models · 81.8/100 Writing Score · $0.022 per script1 configuration on the board

Picks and Verdict

PickKimi K3.1 Pro

Kimi K3.1 Pro (max)

Pick Kimi K3.1 Pro (max) for a script you'll publish, 92 Elo above GLM with separate ranges and 5.4 points ahead on substance, at $0.251.

PickGLM-5.3 Flash

GLM-5.3 Flash (max)

Pick GLM-5.3 Flash (max) for drafts and volume at $0.022 a script, with slightly better tone and length than Kimi's only setting.

GLM-5.3 Flash gets closer to Kimi K3.1 Pro than its price suggests, but the board still puts Kimi ahead. Kimi K3.1 Pro (max) sits 92 Elo above GLM-5.3 Flash (max), and their 95% ranges sit 13 Elo apart: the #7 model of 83 against the #13 model, each ranked by its best setting. That's a real gap, but a narrow one. Both run a single setting called max and take about the same time, 5.5 minutes against 5.2, while GLM spends nearly twice the reasoning, 37,224 tokens against 19,487. Kimi's lead comes from the facts and the visuals: 5.4 points more on substance, 6.9 more on visual cues, and nine of the ten scripts. GLM leads five of the nine metrics, all by less than two points, including tone, YouTube best practices and length. GLM costs $0.022 a script, and Kimi costs about 11 times that at $0.251. For a script I'm going to record, I'd pay for Kimi and its facts. For drafts and volume, GLM is a touch closer to my voice for about two cents.

Disclosure: GLM-5.3 Flash comes from the same lab as one of the four judges, GLM 5.3 Flash. 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 Kimi K3.1 Pro and GLM-5.3 Flash, 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).
Kimi K3.1 ProGLM-5.3 Flash
ConfigurationWriting Elo95% RangeWriting ScoreCost / ScriptTime / ScriptReasoning TokensConfiguration Rank
Kimi K3.1 Pro (max)22052166 to 224682.5$0.2515.5 min19,487#14
GLM-5.3 Flash (max)21132067 to 215381.8$0.0225.2 min37,224#24

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

Kimi K3.1 Pro (max)GLM-5.3 Flash (max)Solid bar: higher score in that row

Kimi K3.1 Pro (max) scores higher on four of the nine metrics and GLM-5.3 Flash (max) on five. Weighted by each metric's share of the Writing Score, Substance, Accuracy & Value does the most to put Kimi K3.1 Pro (max) ahead, with a 5.4-point lead on that metric. The weight beside each metric is its share of the Writing Score.

Tone & Voice Match19% weight
77.0
78.0
Writing Craft & Clarity13% weight
77.8
78.3
Substance, Accuracy & Value15% weight
88.2
82.8
Continuity & Emotion14% weight
80.8
81.3
YouTube Best Practices12% weight
79.7
80.9
Hook Strength10% weight
83.4
82.8
Length Adherence8% weight
95.4
97.1
Slop Score5% weight
85.0
83.1
Visual Cue Quality4% weight
84.9
78.0

Consistency Across Drafts

Kimi K3.1 Pro (max)GLM-5.3 Flash (max)
Score spread across drafts (±)1.651.62
Lowest script score80.4 Script 780.3 Script 4
Highest script score85.5 Script 983.8 Script 9
Range across scripts5.13.5

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 Kimi K3.1 Pro (max) minus GLM-5.3 Flash (max), and the higher score is in bold.

ScriptKimi K3.1 Pro (max)GLM-5.3 Flash (max)Gap
Script 1 opinion / warning explainer81.381.1+0.2
Script 2 news-analysis / skeptical explainer83.281.5+1.7
Script 3 personal roadmap / opinion81.981.0+0.9
Script 4 short explainer82.080.3+1.7
Script 5 news-analysis / opinion explainer84.282.1+2.1
Script 6 founder announcement / personal origin story83.082.9+0.1
Script 7 personal technical walkthrough / agentic workflow case study80.483.5-3.1
Script 8 product release announcement / personal observation82.180.8+1.3
Script 9 career guide / hiring analysis85.583.8+1.7
Script 10 engineering process walkthrough / presentation adaptation81.381.2+0.1

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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