Pick this when
Hard work someone will sign. Agentic coding, long projects, detail-heavy writing.
Skip when
Routine volume. You are paying for thoroughness you may not need.
Leads the public Artificial Analysis Intelligence Index. Anthropic still recommends it as the starting point for complex agent work, even though Fable 5 is the named flagship.
Price
- Input / 1M
- $5.00
- Output / 1M
- $25
- Measured task
- $2.34
Flat rate through the full million-token window. Burns more tokens per job than Sol.
Shape
- Context
- 1M
- Max output
- 128K
- Released
- 2026-07
- Tools
- Yes
- Reasoning
- Yes
Scores
Intelligence index63
GPQA Diamond92
Terminal-Bench 2.189
Agentic index56
- Arena
- 2668
- Speed
- 68/s
- GPQA
- 92.4%
- Term.
- 89.1%
- AA Index. The single number most people mean by “how smart.” It is a blend, so a specialist can lose here and still win the job you care about.
- GPQA. A clean test of hard reasoning. PhD experts sit around 65%. It says little about writing, tools, or taste.
- Term.. Closest public proxy for coding agents that live in a terminal. A high index score with a weak terminal score is a warning.
- Arena. Captures taste and usefulness that unit tests miss. Sample size varies by model, so treat gaps under ~100 Elo as noise.
Anthropic · San Francisco. Claude. Opus 5 leads public intelligence rankings. Fable 5 is the named flagship and the expensive one. Sonnet 5 is the daily driver.