Model Comparison
Claude Sonnet 5.5 vs Claude Haiku 5.5
Claude Sonnet 5.5 (max effort) leads Claude Haiku 5.5 (max effort) by 552 Elo, and their 95% ranges sit 460 Elo apart. Among 78 models, each ranked by its best configuration, Claude Sonnet 5.5 is #2 and Claude Haiku 5.5 is #16. Cost per script: $1.38 for Claude Sonnet 5.5 (max effort) and $0.103 for Claude Haiku 5.5 (max effort).
Last updated , from board data generated at 01:13 UTC.
Picks and Verdict
PickClaude Sonnet 5.5
Claude Sonnet 5.5 (max effort)
Pick Claude Sonnet 5.5 (max effort) for the final script: at $1.38 it sits 213 Elo above xhigh, with separate ranges.
PickClaude Haiku 5.5
Claude Haiku 5.5 (xhigh)
Pick Claude Haiku 5.5 (xhigh) for cheap drafts at $0.029 a script and 3.6 minutes, since it ranks above Sonnet at medium and low for less than half their price.
Same family, and the pricier model wins at every level name the two share, from low to max, each time with ranges that don't overlap. For a script going on camera, it's Claude Sonnet 5.5, the #2 model of 78 against the #16 model: its max effort sits at 2561 Elo against 2009 for Claude Haiku 5.5 (max effort). The settings in between tell me more. Claude Sonnet 5.5 (high) costs $0.092 and takes a minute, while Haiku at max effort costs $0.103 and takes 12.6. Their ranges overlap, so the board cannot order those two, and I'd take the cheaper, faster one, even if Haiku's top setting holds the target length better. Haiku earns its place lower down. Claude Haiku 5.5 (xhigh) at $0.029 sits above Sonnet at medium and low for less than half their price, with a range that clears low and overlaps medium. I'd stop there. Haiku's max effort adds 82 Elo with a separate range, but it costs about 3.6 times as much, and at that price Sonnet at high is the better buy. Cheap drafts on Haiku at xhigh, the real script on Sonnet.
Disclosure: both models come from the same lab as one of the four judges, Claude Opus 5.5. The other judges sit outside that lab, so 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 Claude Haiku 5.5, scored on the same 10 scripts by the same four judges.
- 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).
Shaded rows are the configurations chosen for the metric comparison below.
| Configuration | Writing Elo | 95% Range | Writing Score | Cost / Script | Time / Script | Configuration Rank |
|---|---|---|---|---|---|---|
| Claude Sonnet 5.5 (max effort) | 2561 | 2504 to 2614 | 84.6 | $1.38 | 14.3 min | #3 |
| Claude Sonnet 5.5 (xhigh) | 2348 | 2304 to 2383 | 83.2 | $0.302 | 3.1 min | #10 |
| Claude Sonnet 5.5 (high) | 2040 | 1984 to 2087 | 81.0 | $0.092 | 1.0 min | #27 |
| Claude Haiku 5.5 (max effort) | 2009 | 1972 to 2044 | 80.8 | $0.103 | 12.6 min | #31 |
| Claude Haiku 5.5 (xhigh) | 1927 | 1883 to 1965 | 80.0 | $0.029 | 3.6 min | #41 |
| Claude Sonnet 5.5 (medium) | 1856 | 1812 to 1900 | 79.4 | $0.065 | 0.6 min | #47 |
| Claude Sonnet 5.5 (low) | 1808 | 1771 to 1843 | 78.9 | $0.061 | 0.7 min | #50 |
| Claude Haiku 5.5 (high) | 1723 | 1679 to 1760 | 78.0 | $0.012 | 1.5 min | #53 |
| Claude Haiku 5.5 (medium) | 1620 | 1572 to 1670 | 76.7 | $0.0067 | 0.8 min | #62 |
| Claude Haiku 5.5 (low) | 1504 | 1461 to 1550 | 75.2 | $0.0045 | 0.5 min | #74 |
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.
- Best Configurations Head to Head. Claude Sonnet 5.5 (max effort) leads Claude Haiku 5.5 (max effort) by 552 Elo, and their 95% ranges do not overlap (2504 to 2614 against 1972 to 2044), which is strong evidence for that order.
- Lowest Thinking Levels Head to Head. At their lowest thinking levels, Claude Sonnet 5.5 (low) at Elo 1808 and $0.061 per script leads Claude Haiku 5.5 (low) at Elo 1504 and $0.0045 per script by 304 Elo. Their 95% ranges do not overlap.
- Same Level Name, Side by Side. Claude Sonnet 5.5 has the higher Writing Elo at every level name both models use: low, medium, high, xhigh, and max. The 95% ranges do not overlap at any of them. Level names come from each provider, so the same name does not promise the same reasoning budget.
- Cheapest Claude Sonnet 5.5 Configuration Above Claude Haiku 5.5's Best. The cheapest Claude Sonnet 5.5 configuration with a higher Writing Elo than Claude Haiku 5.5 (max effort), at Elo 2009 and $0.103 per script, is Claude Sonnet 5.5 (high), at Elo 2040 and $0.092 per script. Their 95% ranges overlap, so the board cannot separate them. It costs less than the configuration it beats.
- Lowest to Highest Thinking Level. Claude Sonnet 5.5 moves +753 Elo from low to max effort, at about 23 times the cost per script. Claude Haiku 5.5 moves +505 Elo from low to max effort, at about 23 times the cost per script.
Writing Elo at Each Shared Level Name
| Level | Claude Sonnet 5.5 | Claude Haiku 5.5 | Gap | 95% Ranges |
|---|---|---|---|---|
| low | 1808 | 1504 | +304 | Separate |
| medium | 1856 | 1620 | +236 | Separate |
| high | 2040 | 1723 | +317 | Separate |
| xhigh | 2348 | 1927 | +421 | Separate |
| max | 2561 | 2009 | +552 | Separate |
Gap is Claude Sonnet 5.5 minus Claude Haiku 5.5 at the same level name, using each model's highest-rated configuration at that level.
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) scores higher on all nine metrics. Weighted by each metric's share of the Writing Score, Continuity & Emotion does the most to put Claude Sonnet 5.5 (max effort) ahead, with a 5.8-point lead on that metric. The weight beside each metric is its share of the Writing Score.
Consistency Across Drafts
| Claude Sonnet 5.5 (max effort) | Claude Haiku 5.5 (max effort) | |
|---|---|---|
| Score spread across drafts (±) | 1.22 | 1.55 |
| Lowest script score | 83.0 Script 10 | 78.2 Script 10 |
| Highest script score | 86.7 Script 9 | 82.6 Script 4 |
| Range across scripts | 3.7 | 4.4 |
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 Claude Haiku 5.5 (max effort), and the higher score is in bold.
| Script | Claude Sonnet 5.5 (max effort) | Claude Haiku 5.5 (max effort) | Gap |
|---|---|---|---|
| Script 1 opinion / warning explainer | 84.2 | 80.3 | +3.9 |
| Script 2 news-analysis / skeptical explainer | 84.8 | 80.7 | +4.1 |
| Script 3 personal roadmap / opinion | 84.0 | 80.8 | +3.2 |
| Script 4 short explainer | 85.0 | 82.6 | +2.4 |
| Script 5 news-analysis / opinion explainer | 84.8 | 81.7 | +3.1 |
| Script 6 founder announcement / personal origin story | 84.6 | 81.1 | +3.5 |
| Script 7 personal technical walkthrough / agentic workflow case study | 85.0 | 80.0 | +5.0 |
| Script 8 product release announcement / personal observation | 83.9 | 81.3 | +2.6 |
| Script 9 career guide / hiring analysis | 86.7 | 81.5 | +5.2 |
| Script 10 engineering process walkthrough / presentation adaptation | 83.0 | 78.2 | +4.8 |
Scorecards and Thinking Pages
Each configuration name in the table above opens its own scorecard.
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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