Claude
Claude

Claude Opus 4.5

Model ID:claude-opus-4-5-20251101
2025-11-24Proprietary Model

Claude Opus 4.5 is Anthropic’s frontier reasoning model optimized for complex software engineering, agentic workflows, and long-horizon computer use. It offers strong multimodal capabilities, competitive performance across real-world coding and reasoning benchmarks, and improved robustness to prompt injection. The model is designed to operate efficiently across varied effort levels, enabling developers to trade off speed, depth, and token usage depending on task requirements. It comes with a new parameter to control token efficiency, which can be accessed using the OpenRouter Verbosity parameter with low, medium, or high. Opus 4.5 supports advanced tool use, extended context management, and coordinated multi-agent setups, making it well-suited for autonomous research, debugging, multi-step planning, and spreadsheet/browser manipulation. It delivers substantial gains in structured reasoning, execution reliability, and alignment compared to prior Opus generations, while reducing token overhead and improving performance on long-running tasks.

Claude ProClaude Max (5x)Claude Max (20x)|API
Knowledge Cutoff
2025-08-01
Input → Output Format
Context Memory
200KIN64KOUT
Cost/1M Words
$5IN$25OUT

AI Performance Evaluation

Arena Overall Score
1474
±4
As of 2026-04-02
Overall Rank
No.11
37,461 Votes
Arena by Ability
Hard Prompts
1500±5No.7
Expert Knowledge
1505±13No.7
Instruction Following
1486±7No.5
Conversation Memory
1486±8No.9
Creative
1469±9No.6
Coding
1531±8No.5
Math
1472±12No.9
Arena by Occupation
Creative Writing
1466±7No.8
Social Sciences
1491±8No.6
Media
1456±8No.8
Business
1469±8No.16
Healthcare
1491±13No.17
Legal
1487±12No.9
Software
1513±6No.8
Mathematics
1472±15No.13
Overall
AA Intelligence Index
50%↑11%
LiveBench
54%↓4%
ForecastBench
60%↑0%
Reasoning & Math
AA Math Index
91%↑17%
GPQA Diamond
87%↑5%
HLE
28%↑11%
MMLU-Pro
90%↑7%
AIME 2025
91%↑17%
LB Reasoning
48%↓11%
LB Math
64%↓7%
LB Data
44%↓5%
Coding
AA Coding Index
48%↑12%
LiveCodeBench
87%↑22%
LB Coding
78%↑4%
LB Agentic
50%↑8%
TAU2
90%↑20%
TerminalBench
47%↑13%
SciCode
50%↑8%
Language & Instructions
IFBench
58%↑0%
AA-LCR
74%↑11%
Hallucination (HHEM)
11%↑0%
Factual (HHEM)
89%↑0%
LB Language
77%↑7%
LB IF
29%↓22%
Output Speed
Standard Mode
51tok/s↓31
First Output 1.21s
Reasoning Mode
65tok/s↓45
First Output 12.24s