Model Comparison
Claude Opus 5.5 vs Claude Fable 5.2
Overlapping ranges: the best configurations, Claude Opus 5.5 (xhigh) and Claude Fable 5.2 (xhigh), are 31 Elo apart, and their 95% ranges overlap. Among 87 models, each ranked by its best configuration, Claude Opus 5.5 is #1 and Claude Fable 5.2 is #2. Cost per script: $1.00 for Claude Opus 5.5 (xhigh) and $2.22 for Claude Fable 5.2 (xhigh).
Last updated , from board data generated at 17:52 UTC.
Picks and Verdict
PickClaude Opus 5.5
Claude Opus 5.5 (xhigh)
Pick Claude Opus 5.5 (xhigh) for the script you'll record, since its range overlaps Fable's best and it costs $1.00 a script, under half of Fable at xhigh.
PickClaude Fable 5.2
Claude Fable 5.2 (xhigh)
Pick Claude Fable 5.2 (xhigh) when hooks and length matter most, since its 84.0 on Hook Strength and 99.0 on Length Adherence are the best on this page, at $2.22 a script.
This is the closest match-up Claude Fable 5.2 has, and the bill decides it for me. Claude Opus 5.5 is the #1 model of 87 and Fable the #2 model, each ranked by its best setting. Claude Opus 5.5 (xhigh) leads Claude Fable 5.2 (xhigh), Fable's best setting, by 31 Elo in point estimates, with 95% ranges that overlap, though overlap alone does not test their difference. Opus at xhigh costs $1.00 and 6.7 minutes a script, against $2.22 and 7.4 minutes for Fable at xhigh, and Fable trails it by under a point on six metrics while leading hooks by 1.1 and length and visual cues by 0.4 each. Lower down, Claude Fable 5.2 (high) sits 40 Elo above Claude Opus 5.5 (high) with overlapping ranges and lands the length 5.9 points better, but Opus at high costs $0.328 and finishes in about half the time. Fable's xhigh adds 162 Elo over its high with separate ranges, for about 1.8 times the price. Both max settings land below xhigh, 27 Elo for Fable and 5 for Opus, at about 2.6 times the price, so I'd skip them. I'd run Opus at xhigh for the scripts I record and at high for volume.
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 Opus 5.5 and Claude Fable 5.2, 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.
- Each bar describes one configuration. Overlap alone does not establish a tie or decide their order. Comparing these ranges does not directly test the difference between a pair.
- 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 Opus 5.5 (xhigh) | 2704 | 2648 to 2750 | 85.8 | $1.00 | 6.7 min | #1 |
| Claude Opus 5.5 (max effort) | 2699 | 2640 to 2755 | 85.9 | $2.58 | 17.5 min | #2 |
| Claude Fable 5.2 (xhigh) | 2673 | 2630 to 2717 | 85.6 | $2.22 | 7.4 min | #3 |
| Claude Fable 5.2 (max effort) | 2646 | 2599 to 2689 | 85.5 | $5.75 | 19.9 min | #4 |
| Claude Fable 5.2 (high) | 2511 | 2455 to 2555 | 84.8 | $1.22 | 4.0 min | #5 |
| Claude Opus 5.5 (high) | 2471 | 2418 to 2518 | 84.6 | $0.328 | 2.1 min | #8 |
| Claude Opus 5.5 (medium) | 2452 | 2395 to 2504 | 84.5 | $0.310 | 1.9 min | #9 |
| Claude Opus 5.5 (low) | 2425 | 2359 to 2480 | 84.3 | $0.243 | 1.5 min | #10 |
| Claude Fable 5.2 (medium) | 2422 | 2370 to 2469 | 84.3 | $0.561 | 1.8 min | #11 |
| Claude Fable 5.2 (low) | 2415 | 2370 to 2454 | 84.1 | $0.460 | 1.4 min | #12 |
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. The 95% ranges describe individual configurations; overlap alone establishes neither a tie nor an order for a pair.
- Best Configurations Head to Head. Claude Opus 5.5 (xhigh) at Elo 2704 (range 2648 to 2750) and Claude Fable 5.2 (xhigh) at Elo 2673 (range 2630 to 2717) have overlapping 95% ranges.
- Lowest Thinking Levels Head to Head. At their lowest thinking levels, Claude Opus 5.5 (low) at Elo 2425 and $0.243 per script leads Claude Fable 5.2 (low) at Elo 2415 and $0.460 per script by 10 Elo. Their 95% ranges overlap.
- Same Level Name, Side by Side. Across the level names both models use, Claude Opus 5.5 leads at low, medium, xhigh, and max; Claude Fable 5.2 leads at high. The 95% ranges overlap at every one of them. Level names come from each provider, so the same name does not promise the same reasoning budget.
- Cheapest Claude Opus 5.5 Configuration Above Claude Fable 5.2's Best. The cheapest Claude Opus 5.5 configuration with a higher Writing Elo than Claude Fable 5.2 (xhigh), at Elo 2673 and $2.22 per script, is Claude Opus 5.5 (xhigh), at Elo 2704 and $1.00 per script. Their 95% ranges overlap. It costs less than the configuration it beats.
- Lowest to Highest Thinking Level. Claude Opus 5.5 moves +274 Elo from low to max effort, at about 11 times the cost per script. Claude Fable 5.2 moves +231 Elo from low to max effort, at about 13 times the cost per script.
Writing Elo at Each Shared Level Name
| Level | Claude Opus 5.5 | Claude Fable 5.2 | Gap | 95% Ranges |
|---|---|---|---|---|
| low | 2425 | 2415 | +10 | Overlap |
| medium | 2452 | 2422 | +30 | Overlap |
| high | 2471 | 2511 | -40 | Overlap |
| xhigh | 2704 | 2673 | +31 | Overlap |
| max | 2699 | 2646 | +53 | Overlap |
Gap is Claude Opus 5.5 minus Claude Fable 5.2 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 Opus 5.5 (xhigh) scores higher on six of the nine metrics and Claude Fable 5.2 (xhigh) on three. Weighted by each metric's share of the Writing Score, Tone & Voice Match does the most to put Claude Opus 5.5 (xhigh) ahead, with a 0.7-point lead on that metric. The weight beside each metric is its share of the Writing Score.
Consistency Across Drafts
| Claude Opus 5.5 (xhigh) | Claude Fable 5.2 (xhigh) | |
|---|---|---|
| Score spread across drafts (±) | 1.43 | 1.44 |
| Lowest script score | 84.3 Script 10 | 83.6 Script 10 |
| Highest script score | 87.9 Script 7 | 88.0 Script 9 |
| Range across scripts | 3.6 | 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 Opus 5.5 (xhigh) minus Claude Fable 5.2 (xhigh), and the higher score is in bold.
| Script | Claude Opus 5.5 (xhigh) | Claude Fable 5.2 (xhigh) | Gap |
|---|---|---|---|
| Script 1 opinion / warning explainer | 84.4 | 83.7 | +0.7 |
| Script 2 news-analysis / skeptical explainer | 85.6 | 85.4 | +0.2 |
| Script 3 personal roadmap / opinion | 85.7 | 85.5 | +0.2 |
| Script 4 short explainer | 86.2 | 85.4 | +0.8 |
| Script 5 news-analysis / opinion explainer | 85.1 | 86.1 | -1.0 |
| Script 6 founder announcement / personal origin story | 85.6 | 85.9 | -0.3 |
| Script 7 personal technical walkthrough / agentic workflow case study | 87.9 | 87.3 | +0.6 |
| Script 8 product release announcement / personal observation | 85.8 | 85.1 | +0.7 |
| Script 9 career guide / hiring analysis | 87.9 | 88.0 | -0.1 |
| Script 10 engineering process walkthrough / presentation adaptation | 84.3 | 83.6 | +0.7 |
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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