Anthropic

(San Francisco, CA)

www.anthropic.com

Creator of the Claude family; pioneers of adaptive thinking, Enterprise Frontier Safeguards (EFS), and agentic knowledge work.

6 MODELS TRACKEDNEWEST: CLAUDE HAIKU 5.5 · 2W AGO

What is the latest AI model from Anthropic?

Anthropic's primary flagship model is Claude Opus 5.5 (Undisclosed (Anthropic), 1,000,000 tokens context). Released Sept 22, 2026; Anthropic's flagship with Fable-level agentic coding at 40% lower cost than Opus 5 ($4/$20), beating GPT-6 Astra on FrontierCode at a fifth of the cost per task. Their latest release is Claude Haiku 5.5 (Fast Efficient, released 2026-10-07). How we define “latest”

Release Timeline

NEWEST FIRST

October 2026[1 release]

Claude Haiku 5.5

75% CHEAPEROct 7, 2026

Released Oct 7, 2026; fastest Claude to date at $0.10/$0.50 per 1M tokens for prompts up to 100K, scoring 39.2% on Terminal-Bench 4.0.

Fast EfficientOPEN DATASHEET

September 2026[3 releases]

Claude Sonnet 5.5

30% FASTERSep 28, 2026

Released Sept 28, 2026; 70.6% on Terminal-Bench 4.0 versus 10.3% for Sonnet 5, running 30%+ faster at the same $2/$10 pricing.

Fast BalancedOPEN DATASHEET

Claude Opus 5.5

ANTHROPIC FLAGSHIP• FlagshipSep 22, 2026

Released Sept 22, 2026; Anthropic's flagship with Fable-level agentic coding at 40% lower cost than Opus 5 ($4/$20), beating GPT-6 Astra on FrontierCode at a fifth of the cost per task.

Efficient FrontierOPEN DATASHEET

Claude Fable 5.1

REASONING CEILINGSep 1, 2026

Released Sept 1, 2026; Anthropic's capability ceiling for agentic coding and knowledge work, with 75% cheaper cache reads and 52.6% on Terminal-Bench-Science.

Adaptive ReasoningOPEN DATASHEET

August 2026[1 release]

Claude Sonnet 5

PRODUCTION DEFAULTAug 6, 2026

The recommended default for coding, writing, and production agents; top tool-call reliability for structured workflows.

Balanced ProductionOPEN DATASHEET

July 2026[1 release]

Claude Opus 5

HEAVYWEIGHT AGENTICJul 15, 2026

Deep multi-hour research, complex code synthesis, and long-horizon workflow orchestration.

Deep ResearchOPEN DATASHEET