Claude 4 / Opus 4
Anthropic · May 2025
⚠ deprecatedCloseddense transformermultimodalAPI Available
Context Window200K tokens
VariantsOpus 4, Sonnet 4
Sunset DateJune 2026
Why It Matters
Marked the beginning of the 'agentic era' for Claude, with models capable of working independently on complex, long-running tasks for hours. Opus 4 set new standards for AI-assisted software engineering.
Description
Major generational leap that introduced 'extended thinking' — the ability to reason through complex problems step-by-step before responding. Opus 4 became widely regarded as the most capable coding model available, with strong performance on sustained, multi-hour agentic tasks. Also launched 'Claude Code,' a dedicated coding assistant.
Notable Milestones
- ▸Powers Claude Code for autonomous software development
- ▸First Claude model with extended thinking for multi-step reasoning
- ▸Used for sustained 30+ hour agentic coding sessions
Benchmark Scores
SWE-benchReal-world software engineering
72.0%Key Innovations
Agentic
AgenticModels that can autonomously plan, execute multi-step tasks, use tools, and self-correct without human intervention.
Reasoning
ReasoningStructured step-by-step problem solving, often using chain-of-thought or tree-of-thought approaches.
Code Gen
Code GenAbility to write, debug, and understand programming code across multiple languages.
Test-Time Compute
Test-Time ComputeUsing extra computation during inference (not training) to improve answer quality — thinking longer on harder problems.
Family Tree
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Successors (2)
Enabled By
B100 / B200NVIDIA · March 2024
2.5x H100