LLM Comparison

Claude Opus 5.5 vs Claude Fable 5.1: benchmark scores, pricing & comparison.

Side-by-side Claude Opus 5.5 vs Claude Fable 5.1 comparison across SWE-bench, GPQA, HLE, Terminal-Bench, coding agent scores, token pricing, context window, and AskClash RWT. Green marks the winner on each benchmark.

Verdict: Claude Opus 5.5 ranks higher (#1 vs #2) and wins 5 of 9 shared benchmarks; Claude Opus 5.5 costs less ($4.00/$20.0 vs $10.0/$50.0 per 1M tokens).

Open live leaderboardClaude Opus 5.5 model pageClaude Fable 5.1 model page
Rank #1 vs #2AskClash overall scores 81.1 vs 78.6.
Pricing $4.00/$20.0 vs $10.0/$50.0Input and output token prices per 1M tokens when published.
Proprietary vs ProprietaryAnthropic vs Anthropic.

Claude Opus 5.5 vs Claude Fable 5.1 benchmark comparison

Green cells highlight the winning model for each metric. Scores are cached from the AskClash LLM leaderboard snapshot.

MetricClaude Opus 5.5Claude Fable 5.1
Overall Score81.178.6
Leaderboard Rank#1#2
ACB76.579.2
RWT—9.0
Coding Agent Index—62.2
HLE67.765.0
GPQA—93.7
SWE-Pro89.981.2
SWE-Atlas—64.8
Terminal-Bench59.652.0
DeepSWE74.267.4
GDPval-AA1846.21853.0
Finance Agent58.658.9
MMMU-Pro87.790.6
ARC-AGI 291.790.0
Input Price (per 1M tokens)$4.00$10.0
Output Price (per 1M tokens)$20.0$50.0
Context Window1M1M
Benchmarks Published1215

Claude Opus 5.5 vs Claude Fable 5.1 head-to-head charts

Claude Opus 5.5 leads 6 and Claude Fable 5.1 leads 4 of 10 shared benchmarks. Claude Opus 5.5 is cheaper on a defined 1M-input / 200K-output workload. Charts show only benchmarks both models publish.

Claude Opus 5.5Claude Fable 5.1
Overall
81.1Claude Opus 5.5
78.6Claude Fable 5.1
ACB
76.5Claude Opus 5.5
79.2Claude Fable 5.1
HLE
67.7Claude Opus 5.5
65.0Claude Fable 5.1
SWE-Pro
89.9Claude Opus 5.5
81.2Claude Fable 5.1
Terminal-Bench
59.6Claude Opus 5.5
52.0Claude Fable 5.1
DeepSWE
74.2Claude Opus 5.5
67.4Claude Fable 5.1
GDPval-AA
1846.2Claude Opus 5.5
1853.0Claude Fable 5.1
Finance Agent
58.6Claude Opus 5.5
58.9Claude Fable 5.1
MMMU-Pro
87.7Claude Opus 5.5
90.6Claude Fable 5.1
ARC-AGI 2
91.7Claude Opus 5.5
90.0Claude Fable 5.1
Claude Opus 5.5
Input$4.00
Output$20.0
Workload$8.00
Context1M
Claude Fable 5.1
Input$10.0
Output$50.0
Workload$20
Context1M

Workload = published cost of 1M input + 200K output tokens. Open the live leaderboard for interactive compare charts.

More Claude Opus 5.5 and Claude Fable 5.1 comparisons

Explore how Claude Opus 5.5 and Claude Fable 5.1 stack up against other top-ranked LLMs.

Claude Opus 5.5 vs Claude Opus 5Claude Fable 5.1 vs Claude Opus 5Claude Opus 5.5 vs Claude Sonnet 5.5Claude Fable 5.1 vs Claude Sonnet 5.5Claude Opus 5.5 vs Claude Fable 5Claude Fable 5.1 vs Claude Fable 5Claude Opus 5.5 vs GPT-6.1 SolClaude Fable 5.1 vs GPT-6.1 SolClaude Opus 5.5 vs GPT-6 AstraClaude Fable 5.1 vs GPT-6 Astra

How to read this comparison

Benchmark scores

Higher is better for all benchmark scores (SWE-bench, GPQA, HLE, Terminal-Bench, etc.). Green marks the model with the higher score.

Token pricing

Lower is better for input and output prices. Green marks the cheaper model per 1M tokens.

Coverage matters

Models with fewer disclosed benchmark cells may have inflated percentile scores. Check the benchmark cell count for context.

This comparison page is generated from the AskClash LLM leaderboard cache. Open the live leaderboard for real-time scores and interactive filtering.