This model is deprecated. We still benchmark its performance, but less often: every 18 hours instead of every 6.
Anthropic has launched a newer release, Claude Sonnet 4.6. We suggest considering it instead.
Claude 4.5 Sonnet: Intelligence, Performance & Price Analysis
Available providers
Model summary
Verbosity
Claude 4.5 Sonnet (Reasoning) supports text and image input, outputs text, and has a 1M tokens context window with knowledge up to July 2025.
Pricing for Claude 4.5 Sonnet (Reasoning) is $3.00 per 1M input tokens (somewhat expensive, median: $2.00) and $15.00 per 1M output tokens (somewhat expensive, median: $10.00).
| Input modality | Supports: text and image |
|---|---|
| Output modality | Supports: text |
| Knowledge cutoff | Jul 1, 2025 |
| Context window | 1M ~1500 A4 pages of size 12 Arial font |
Metrics are compared against models of the same class:
- Non-reasoning models → compared only with other non-reasoning models
- Reasoning models → compared across both reasoning and non-reasoning
- Open weights models → compared only with other open weights models of the same size class:
- Tiny: ≤4B parameters
- Small: 4B–40B parameters
- Medium: 40B–150B parameters
- Large: >150B parameters
- Proprietary models → compared across proprietary and open weights models of the same price range, using a blended 3:1 input/output price ratio:
- <$0.15 per 1M tokens
- $0.15–$1 per 1M tokens
- >$1 per 1M tokens
Intelligence
Artificial Analysis Intelligence Index
Artificial Analysis Intelligence Index by Open Weights / Proprietary
Intelligence Index vs. Cost per Task
Evaluations
Agentic knowledge work, Elo
Agentic SaaS workflows
Professional document reasoning, All-pass
Agentic coding & terminal use
Agentic real-world work tasks, Elo
Medical long context reasoning
Visual reasoning
Cost
Cost per Intelligence Index Task
Cost to Run Artificial Analysis Intelligence Index
Pricing: Cache Hit, Input, and Output
Performance
Measured by time per task (minutes), output speed (tokens per second), time to first answer token and time to first token (seconds)
Time per Intelligence Index Task
Output Speed
Time to First Answer Token
Context Window
Context Window
Further details
Weights | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Claude 4.5 Sonnet (Reasoning) | - | - | 1M | $2.31 | - | 51 | Not available | ||
| Claude 4.5 Sonnet (Non-reasoning) | - | - | 1M | $2.31 | - | 50 | Not available |
Frequently Asked Questions
Common questions about Claude 4.5 Sonnet
Claude 4.5 Sonnet was released on September 29, 2025.
Claude 4.5 Sonnet was created by Anthropic.
Claude 4.5 Sonnet has a time to first answer token of 16.86s (reasoning) and 1.44s (non-reasoning) (based on Anthropic's API). Claude 4.5 Sonnet (Reasoning)'s time to first answer token is somewhat higher than average compared to other models in a similar price tier (median: 14.04s).
Claude 4.5 Sonnet costs $3.00 per 1M input tokens (somewhat higher than average, median: $2.00) and $15.00 per 1M output tokens (somewhat higher than average, median: $10.00), based on Anthropic's API.
Claude 4.5 Sonnet costs $3.00 per 1M input tokens and $15.00 per 1M output tokens (based on Anthropic's API). For a blended rate (7:2:1 cache hit/input/output ratio), this is $2.31 per 1M tokens. Pricing may vary by provider. Compare provider pricing
Yes, Claude 4.5 Sonnet (Reasoning) is a reasoning model. It uses extended thinking or chain-of-thought reasoning to work through complex problems before providing an answer. No, Claude 4.5 Sonnet (Non-reasoning) is not a reasoning model. It provides direct responses without extended chain-of-thought reasoning.
Claude 4.5 Sonnet supports text and image input.
Claude 4.5 Sonnet supports text output.
Yes, Claude 4.5 Sonnet supports image input and can analyze, describe, and answer questions about images.
Yes, Claude 4.5 Sonnet is multimodal. It can process text and image input and generate text output.
Claude 4.5 Sonnet has a context window of 1M tokens. This determines how much text and conversation history the model can process in a single request.
No, Claude 4.5 Sonnet is proprietary. The model weights are not publicly available.
Claude 4.5 Sonnet is a proprietary model and Anthropic has not disclosed the model size or parameter count.
Claude 4.5 Sonnet has a knowledge cutoff of July 2025. The model's training data includes information up to this date.
Yes, Claude 4.5 Sonnet is available via API through 4 providers. Compare API providers
Claude 4.5 Sonnet is available through 4 API providers. Compare providers