DeepSeek V4 Flash (Reasoning, Max Effort) vs. Claude Opus 4.5 (Reasoning)
Comparison between DeepSeek V4 Flash (Reasoning, Max Effort) and Claude Opus 4.5 (Reasoning) across intelligence, price, speed, context window and more.
For details relating to our methodology, see our Methodology page.
Highlights
Model Comparison
DeepSeek V4 Flash (Reasoning, Max Effort) | Claude Opus 4.5 (Reasoning) | ||
|---|---|---|---|
| Intelligence Index | 40 | 41* | Claude Opus 4.5 (Reasoning) is more intelligent than DeepSeek V4 Flash (Reasoning, Max Effort) |
| Price per 1M Tokens | $0.06 | $3.85 | DeepSeek V4 Flash (Reasoning, Max Effort) is cheaper than Claude Opus 4.5 (Reasoning) |
| Output Speed | 120 tokens/s | 47 tokens/s | DeepSeek V4 Flash (Reasoning, Max Effort) is faster than Claude Opus 4.5 (Reasoning) |
| Time to First Token | 1.22s | 12.85s | DeepSeek V4 Flash (Reasoning, Max Effort) responds faster than Claude Opus 4.5 (Reasoning) |
| Context Window | 1000k tokens~1500 A4 pages of size 12 Arial font | 200k tokens~300 A4 pages of size 12 Arial font | DeepSeek V4 Flash (Reasoning, Max Effort) has a larger context window than Claude Opus 4.5 (Reasoning) |
| Release Date | April, 2026 | November, 2025 | DeepSeek V4 Flash (Reasoning, Max Effort) has a more recent release date than Claude Opus 4.5 (Reasoning) |
| Reasoning | Yes | Yes | Both DeepSeek V4 Flash (Reasoning, Max Effort) and Claude Opus 4.5 (Reasoning) have reasoning |
| Image Input Support | No | Yes | Claude Opus 4.5 (Reasoning) has image input support while DeepSeek V4 Flash (Reasoning, Max Effort) does not |
| Open Source (Weights) | No | DeepSeek V4 Flash (Reasoning, Max Effort) is open source while Claude Opus 4.5 (Reasoning) is proprietary |
IntelligenceUpdated
Artificial Analysis Intelligence Index
Artificial Analysis Intelligence Index by Open Weights / Proprietary
Intelligence Evaluations
Agentic real-world work tasks, (Elo-500)/2000
Agentic tool use
Agentic coding & terminal use
Coding
Reasoning & knowledge
Scientific reasoning
Physics reasoning
Knowledge
1 - hallucination rate
Long context reasoning
Agentic knowledge work, Elo
Agentic SaaS workflows
Legal agentic work, criterion pass rate
Agentic business operations
Instruction following
Long-horizon agentic tasks
Kubernetes incident root-cause analysis
Visual reasoning
AA-BriefcaseNew
AA-Briefcase Elo
AA-Omniscience
AA-Omniscience Index
Openness
Artificial Analysis Openness Index: Score
Intelligence Index Comparisons
Intelligence vs. Cost per Intelligence Index Task
Token Use
Output Tokens per Intelligence Index Task
Price and Cost
Cost per Intelligence Index Task
Cost to Run Artificial Analysis Intelligence Index
Pricing: Cache Hit, Input, and Output
Context Window
Context Window
Speed
Measured by Output Speed (tokens per second)
Output Speed
Time per Intelligence Index Task
Latency
Measured by Time (seconds) to First Token
Latency: Time To First Answer Token
End-to-End Response Time
Seconds to output 500 tokens, calculated based on time to first token, 'thinking' time for reasoning models, and output speed
End-to-End Response Time
Model Size (Open Weights Models Only)
Model Size: Total and Active Parameters
Frequently Asked Questions
Claude Opus 4.5 (Reasoning) is more intelligent. Claude Opus 4.5 (Reasoning) scores 41 (estimated), compared with DeepSeek V4 Flash (Reasoning, Max Effort) at 40 on the Artificial Analysis Intelligence Index.
DeepSeek V4 Flash (Reasoning, Max Effort) is faster. DeepSeek V4 Flash (Reasoning, Max Effort) generates 120.4 tokens per second, compared with Claude Opus 4.5 (Reasoning) at 47.1 tokens per second.
DeepSeek V4 Flash (Reasoning, Max Effort) is cheaper. DeepSeek V4 Flash (Reasoning, Max Effort) costs $0.06 per 1M tokens, compared with Claude Opus 4.5 (Reasoning) at $3.85 per 1M tokens (7:2:1 cache hit/input/output ratio).
DeepSeek V4 Flash (Reasoning, Max Effort) has lower latency. DeepSeek V4 Flash (Reasoning, Max Effort) has a time to first token of 1.22s, compared with Claude Opus 4.5 (Reasoning) at 12.85s.
DeepSeek V4 Flash (Reasoning, Max Effort) has a larger context window. DeepSeek V4 Flash (Reasoning, Max Effort) supports 1.0M tokens, compared with Claude Opus 4.5 (Reasoning) at 200k tokens.