Claude Opus 4.8
Parameters
-
Context Length
1M
Modality
Multimodal
Architecture
Dense
License
Proprietary
Release Date
28 May 2026
Knowledge Cutoff
-
Evaluation Benchmarks
Rank
#2
| Benchmark | Score | Rank |
|---|---|---|
Web Development WebDev Arena | 1559 | 🥉 3 |
General Text Text Arena | 1486 | ⭐ 5 |
Rankings
Overall Rank
#2 🥈
Coding Rank
#11
About Claude Opus 4.8
Anthropic's flagship model released May 28, 2026. Built on the Opus 4 architecture with significant improvements in coding agent performance and judgment quality. Opus 4.8 is approximately four times less likely to allow flaws in code it has written to pass unremarked compared to its predecessor. It introduces Dynamic Workflows in Claude Code, enabling hundreds of parallel subagents in a single session for codebase-scale migrations. Features a 1M token context window, adaptive thinking support, and is priced at $5/M input tokens and $25/M output tokens.
Technical Specifications
Attention
Attention Structure
Multi-Head Attention
Attention Heads
-
Key-Value Heads
-
Attention Head Dimension
-
Position Embedding
Absolute Position Embedding
RoPE Theta
-
Sliding Window Attention
-
Sliding Window Size
-
Sliding Window Ratio
-
Linear Attention
-
Linear Attention Ratio
-
Normalization
-
Activation Function
-
Dimensions
Hidden Dimension Size
-
Number of Layers
-
FFN Intermediate Size (Dense)
-
Multi-Token Prediction Heads
-
Tokenizer
Vocabulary Size
-
Resources
About Claude Opus 4.8
The Claude Opus 4.8 generation represents Anthropic's most capable Opus-class model, built for complex reasoning, long-horizon agentic coding, and high-autonomy professional work. It introduces a major leap in judgment quality and multi-agent coordination, with the ability to run hundreds of parallel subagents simultaneously through the Dynamic Workflows feature in Claude Code.
Other Claude Opus 4.8 Models
- No related models available