Claude Sonnet 4.5
Claude Sonnet 4.5 is worth evaluating for coding, rag, and agents when its provider route and context window match the workload.
Use it for
- Teams evaluating coding, rag, and agents
- Workloads that can use a 200k context window
- Buyers comparing 4 tracked provider routes
Do not use it for
- Workloads where another current model has stronger sourced task evidence
- Family
- Claude 4.5
- Released
- 2025-09-29
- Context
- 200k
- Architecture
- Decoder Only
- Knowledge cutoff
- 2025-12
- Specialization
- general
- Openness
- Proprietary
- License
- ProprietaryCommercial use: conditional
- Training
- Fine-tuned
Cheapest of 8 routes · Anthropic
About
Claude Sonnet 4.5 is Anthropic's Claude 4.5 model with multimodal text and image input and an optional reasoning mode. It offers a 200K-token context window and scores 86 on MMLU PRO.
Claude Sonnet 4.5 is a proprietary model in the Claude 4.5 family. The structured metadata tracks a 200k-token context window, multimodal input, reasoning, function calling, tool use, and structured outputs. This page tracks provider routes through Microsoft Foundry, Anthropic, Snowflake Cortex, and 5 more, with the cheapest tracked route listed at $3 input and $15 output per 1M tokens. Headline tracked benchmarks include Massive Multi-discipline Multimodal Understanding 77.8, BFCL 73.2, and MMLU PRO 86.0.
Top use-case fit: coding, agents, and build tasks
Coding
Q/$ D1 relevant benchmark in the decision map.
RAG
Included by capability and metadata signals in the decision map.
Agents
Q/$ D1 relevant benchmark in the decision map.
Provider price ladder
Compare all 8Compare API pricing across 4 providers for input and output tokens, batch, and cached reads when available.
| Provider | Input / 1M | Output / 1M | Batch in / out | Cache | Route |
|---|---|---|---|---|---|
| Anthropic | $3.00 | $15.00 | $1.50 / $7.50 | - | Serverless |
| GCP Vertex AI | $3.00 | $15.00 | - | - | Serverless |
| Microsoft Foundry | $3.00 | $15.00 | - | read $0.300 / 5m $3.75 / 1h $6.00 | ServerlessProvisioned |
| OpenRouter | $3.00 | $15.00 | - | - | Serverless |
Available via routers & gateways(16)
LiteLLM
GatewayOpen-source Python SDK and proxy server that unifies 100+ LLM APIs behind a single OpenAI-compatible interface, with load balancing, cost tracking, and configurable failover.
OpenRouter
HybridUnified hybrid gateway to 400+ models from 60+ providers via a single OpenAI-compatible API, with optional auto-routing that selects the best model per prompt.
Portkey
GatewayProduction AI gateway routing to 1,600+ LLMs with failover, load balancing, semantic caching, and guardrails; Apache 2.0 core is fully self-hostable with the complete feature set.
AIRouter
RouterCommercial LLM router that analyzes incoming requests and routes to the optimal model for cost/quality/latency via a drop-in OpenAI-compatible API, with a privacy-preserving embedding mode that avoids sending prompt content.
Amazon Bedrock Intelligent Prompt Routing
RouterAWS Bedrock's native intelligent prompt router that routes prompts between Anthropic Claude model tiers (Haiku/Sonnet) based on predicted task complexity, with no extra per-routing charge.
Azure AI Foundry Model Router
RouterMicrosoft Azure AI Foundry's native model router that uses a trained ML model to route each prompt in real time to the optimal Azure-hosted model, with Balanced/Cost/Quality mode selection and automatic failover.
Capabilities
Benchmark peer barsfor Coding
Benchmark scores(6)
| Benchmark | Score | Version | Source |
|---|---|---|---|
| Massive Multi-discipline Multimodal Understanding | 77.8 | — | https://mmmu-benchmark.github.io/ |
| BFCL | 73.2 | — | https://gorilla.cs.berkeley.edu/leaderboard.html |
| MMLU PRO | 86.0 | — | https://huggingface.co/spaces/TIGER-Lab/MMLU-Pro |
| MMMU Pro | 68.9 | official Anthropic (comparison model in Opus 4.6 system card), with image cropping tool | https://www.anthropic.com/claude-opus-4-6-system-card |
| SWE-bench Verified | 77.2 | — | https://www.anthropic.com/news/claude-sonnet-4-5 |
| Google-Proof Q&A | 83.4 | — | https://www.anthropic.com/news/claude-sonnet-4-5 |
Migration checks
No linked migration route is available for this model yet.
Rankings & picks(2)
Compare Claude Sonnet 4.5 with other models
Comparison and alternatives
Browse all comparisons →Show all 65 popular comparisonssorted by 7-day search impressions
Frequently asked questions
What is the context window of Claude Sonnet 4.5?
Claude Sonnet 4.5 has a context window of 200k tokens.
How much does Claude Sonnet 4.5 cost?
Claude Sonnet 4.5 pricing ranges from $3/1M to $9.0/1M input tokens depending on the provider.
When was Claude Sonnet 4.5 released?
Claude Sonnet 4.5 was released on 2025-09-29.
Which providers offer Claude Sonnet 4.5?
Claude Sonnet 4.5 is available from 8 providers: Microsoft Foundry, Anthropic, Snowflake Cortex, GCP Vertex AI, AWS Bedrock, Replicate API, OpenRouter, Vercel AI Gateway.
What benchmarks has Claude Sonnet 4.5 been tested on?
Claude Sonnet 4.5 has been evaluated on 6 benchmarks, including Massive Multi-discipline Multimodal Understanding, BFCL, MMLU PRO, MMMU Pro, SWE-bench Verified.
Cheapest of 8 routes · Anthropic