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Model Comparison

Claude Sonnet 5.5 vs MiMo-V2.6-Pro UltraSpeed

Claude Sonnet 5.5 (max effort) leads MiMo-V2.6-Pro UltraSpeed (thinking on) by 564 Elo, and their 95% ranges sit 467 Elo apart. Among 78 models, each ranked by its best configuration, Claude Sonnet 5.5 is #2 and MiMo-V2.6-Pro UltraSpeed is #17. Cost per script: $1.38 for Claude Sonnet 5.5 (max effort) and $0.177 for MiMo-V2.6-Pro UltraSpeed (thinking on).

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
MiMo-V2.6-Pro UltraSpeed
1997 Writing Elo of MiMo-V2.6-Pro UltraSpeed (thinking on), its best configuration#17 of 78 models · 80.6/100 Writing Score · $0.177 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 everyday scripts, 351 Elo above MiMo with separate ranges for $0.302.

PickMiMo-V2.6-Pro UltraSpeed

MiMo-V2.6-Pro UltraSpeed (thinking on)

Pick MiMo-V2.6-Pro UltraSpeed (thinking on) when you need a draft back in half a minute, since the board can't separate it from Sonnet at high, which takes twice as long.

MiMo-V2.6-Pro UltraSpeed earns its name at half a minute per script, and speed is the main thing it has over Claude Sonnet 5.5. At the top the gap is clear: Claude Sonnet 5.5 (max effort) sits at 2561 Elo against MiMo's 1997, with ranges far apart, and that's the #2 model of 78 against the #17 model, each ranked by its best setting. Lower down it gets close. Claude Sonnet 5.5 (high) sits 43 Elo above MiMo with overlapping ranges, so the board cannot separate them, and Sonnet costs $0.092 there against $0.177. MiMo still writes better visual cues than that Sonnet setting and lands closer to the target length. Sonnet's medium and low settings fall below it, with separate ranges. For a real step up, Claude Sonnet 5.5 (xhigh) is well clear of MiMo for $0.302 and about three minutes. Max effort adds another 213 Elo with separate ranges, at about four and a half times the xhigh price and 14.3 minutes a script. Most of my scripts would go to xhigh, with max effort held back for the ones I care most about.

Disclosure: Claude Sonnet 5.5 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 Sonnet 5.5 and MiMo-V2.6-Pro UltraSpeed, 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 5.5MiMo-V2.6-Pro UltraSpeed
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
Claude Sonnet 5.5 (high)20401984 to 208781.0$0.0921.0 minN/A#27
MiMo-V2.6-Pro UltraSpeed (thinking on)19971954 to 203780.6$0.1770.5 min10,745#34
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)MiMo-V2.6-Pro UltraSpeed (thinking on)Solid bar: higher score in that row

Claude Sonnet 5.5 (max effort) scores higher on all nine metrics. 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 5.1-point lead on that metric. The weight beside each metric is its share of the Writing Score.

Tone & Voice Match19% weight
80.5
78.2
Writing Craft & Clarity13% weight
81.8
78.0
Substance, Accuracy & Value15% weight
87.8
82.7
Continuity & Emotion14% weight
84.5
80.0
YouTube Best Practices12% weight
82.6
78.6
Hook Strength10% weight
81.0
80.6
Length Adherence8% weight
98.8
89.4
Slop Score5% weight
87.8
83.8
Visual Cue Quality4% weight
84.4
79.3

Consistency Across Drafts

Claude Sonnet 5.5 (max effort)MiMo-V2.6-Pro UltraSpeed (thinking on)
Score spread across drafts (±)1.221.87
Lowest script score83.0 Script 1078.5 Script 4
Highest script score86.7 Script 982.3 Script 7
Range across scripts3.73.8

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 Claude Sonnet 5.5 (max effort) minus MiMo-V2.6-Pro UltraSpeed (thinking on), and the higher score is in bold.

ScriptClaude Sonnet 5.5 (max effort)MiMo-V2.6-Pro UltraSpeed (thinking on)Gap
Script 1 opinion / warning explainer84.279.0+5.2
Script 2 news-analysis / skeptical explainer84.880.6+4.2
Script 3 personal roadmap / opinion84.080.9+3.1
Script 4 short explainer85.078.5+6.5
Script 5 news-analysis / opinion explainer84.881.2+3.6
Script 6 founder announcement / personal origin story84.681.2+3.4
Script 7 personal technical walkthrough / agentic workflow case study85.082.3+2.7
Script 8 product release announcement / personal observation83.981.3+2.6
Script 9 career guide / hiring analysis86.782.3+4.4
Script 10 engineering process walkthrough / presentation adaptation83.078.8+4.2

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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