Claude Sonnet 4.5 vs GPT-4 Turbo
Claude Sonnet 4.5 (2025) and GPT-4 Turbo (2024) are frontier reasoning models from Anthropic and OpenAI. Claude Sonnet 4.5 ships a 200K-token context window, while GPT-4 Turbo ships a 128K-token context window. On MMLU PRO, Claude Sonnet 4.5 leads by 16.6 pts. On pricing, Claude Sonnet 4.5 costs $3/1M input tokens versus $5/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit.
Claude Sonnet 4.5 is ~67% cheaper at $3/1M; pay for GPT-4 Turbo only for coding workflow support.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-09-29 | 2024-04-09 |
| Context window | 200K | 128K |
| Parameters | — | 1.76T (8x222B MoE)* |
| Architecture | decoder only | mixture of experts |
| License | Proprietary | Proprietary |
| Knowledge cutoff | 2025-12 | 2023-12 |
Pricing and availability
| Pricing attribute | Claude Sonnet 4.5 | GPT-4 Turbo |
|---|---|---|
| Input price | $3/1M tokens | $5/1M tokens |
| Output price | $15/1M tokens | $15/1M tokens |
| Providers |
Capabilities
| Capability | Claude Sonnet 4.5 | GPT-4 Turbo |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | Yes | No |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | No | Yes |
Benchmarks
| Benchmark | Claude Sonnet 4.5 | GPT-4 Turbo |
|---|---|---|
| MMLU PRO | 86.0 | 69.4 |
Deep dive
On shared benchmark coverage, MMLU PRO has Claude Sonnet 4.5 at 86 and GPT-4 Turbo at 69.4, with Claude Sonnet 4.5 ahead by 16.6 points. The largest visible gap is 16.6 points on MMLU PRO, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.
The capability footprint differs most on reasoning mode: Claude Sonnet 4.5 and code execution: GPT-4 Turbo. Both models share vision, multimodal input, function calling, and tool use, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
For cost, Claude Sonnet 4.5 lists $3/1M input and $15/1M output tokens, while GPT-4 Turbo lists $5/1M input and $15/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Claude Sonnet 4.5 lower by about $1.4 per million blended tokens. Availability is 7 providers versus 5, so concentration risk also matters.
Choose Claude Sonnet 4.5 when reasoning depth, larger context windows, and lower input-token cost are central to the workload. Choose GPT-4 Turbo when coding workflow support are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which has a larger context window, Claude Sonnet 4.5 or GPT-4 Turbo?
Claude Sonnet 4.5 supports 200K tokens, while GPT-4 Turbo supports 128K tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Which is cheaper, Claude Sonnet 4.5 or GPT-4 Turbo?
Claude Sonnet 4.5 is cheaper on tracked token pricing. Claude Sonnet 4.5 costs $3/1M input and $15/1M output tokens. GPT-4 Turbo costs $5/1M input and $15/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is Claude Sonnet 4.5 or GPT-4 Turbo open source?
Claude Sonnet 4.5 is listed under Proprietary. GPT-4 Turbo is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for vision, Claude Sonnet 4.5 or GPT-4 Turbo?
Both Claude Sonnet 4.5 and GPT-4 Turbo expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for multimodal input, Claude Sonnet 4.5 or GPT-4 Turbo?
Both Claude Sonnet 4.5 and GPT-4 Turbo expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Where can I run Claude Sonnet 4.5 and GPT-4 Turbo?
Claude Sonnet 4.5 is available on Microsoft Foundry, Anthropic, Snowflake Cortex, GCP Vertex AI, and AWS Bedrock. GPT-4 Turbo is available on OpenAI API, Azure OpenAI, Salesforce Einstein Generative AI, OpenRouter, and Replicate API. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
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Last reviewed: 2026-05-11. Data sourced from public model cards and provider documentation.