GPT-6 Sol vs Claude Sonnet 5.5
Which one to choose
Pick GPT-6 Sol if you already run GPT-6 and want a model with a reasoning setting of none, or a close step below OpenAI's Astra tier. Pick Claude Sonnet 5.5 for an interactive coding assistant or computer-use workflow where fast replies and fewer tool round-trips matter. The deciding factor is speed against depth: Sonnet 5.5 is Anthropic's speed-focused current Sonnet, while Sol is OpenAI's mid-to-upper model now superseded by GPT-6.1 Sol.
Pricing comparison
| GPT-6 Sol | Claude Sonnet 5.5 | |
|---|---|---|
| Model maker | OpenAI | Anthropic |
| Delivery availability | Available | Available |
| Context window | 1.05M | 1M |
| Max output | 128K | 128K |
| Official price | Input$2.00per 1M tokensOutput$10.00per 1M tokens | Input$2.00per 1M tokensOutput$10.00per 1M tokens |
| TokenLab price | Input$0.60per 1M tokensOutput$3.00per 1M tokens | Input$0.60per 1M tokensOutput$3.00per 1M tokens |
| Model performance |
|
|
| Capabilities | CodeJSON modePrompt CacheReasoningTool useVision | JSON modePrompt CacheReasoningTool useVision |
Choose GPT-6 Sol when
- Your workflow needs the option of no reasoning on simple calls.
- You are upgrading a GPT-5.6 Sol integration and want to measure the change.
- You chain lookups and document edits across internal tools for operations teams.
Choose Claude Sonnet 5.5 when
- A developer waits on each step, so reply speed and fewer tool calls decide the experience.
- You operate web apps and desktop tools from screenshots to file forms and move data.
- You want to reduce up-front thinking with the between_tools setting for faster replies.
How they differ
| Aspect | GPT-6 Sol | Claude Sonnet 5.5 |
|---|---|---|
| Speed emphasis | Built for complex coding and agentic workflows, with depth ahead of speed. | Anthropic describes it as the best mix of speed and intelligence, with fewer tokens per task. |
| Tool-call efficiency | Calls tools alongside images and schema-checked JSON. | Batches tool calls better, so tasks finish in fewer steps. |
| Computer use | OpenAI reports improvements in computer use over the earlier Sol. | Anthropic reports strong screenshot-driven results and lists computer use as a main use. |
| Sampling and tool constraints | Reasoning setting is the main behaviour dial. | Forced tool use returns an error and non-default temperature, top_p or top_k are rejected. |
| Safety limits | No cybersecurity restrictions. | New safeguards restrict some cybersecurity tasks, and higher-risk requests fall back to Sonnet 5. |
Summary
- GPT-6 Sol: Input $0.60 / Output $3.00 per 1M tokens; Claude Sonnet 5.5: Input $0.60 / Output $3.00 per 1M tokens. Rates depend on the billing unit, specification, and usage. Compare matching conditions in the model's detailed pricing; a single rate does not determine the total cost.
FAQ
Is Claude Sonnet 5.5 faster than GPT-6 Sol?
Anthropic positions Sonnet 5.5 around speed and says it generates output more than 30% faster than Sonnet 5, but it does not compare itself with GPT-6 Sol. Measure latency on your own prompts.
Which should I use for a coding assistant?
For interactive use, where the developer waits, Sonnet 5.5 is designed for it. GPT-6 Sol is the better fit for existing GPT-6 deployments, though OpenAI points new projects to GPT-6.1 Sol.
Can I switch between them without prompt changes?
Expect some changes. Sonnet 5.5 rejects forced tool use and non-default sampling values, while Sol uses a reasoning setting that Claude does not have. Test tool loops and output formats.
Do security tasks work on both?
Sonnet 5.5 restricts some cybersecurity requests, and higher-risk ones fall back to Sonnet 5. If you rely on defensive security analysis, test your prompts on both.
Which is cheaper, GPT-6 Sol or Claude Sonnet 5.5?
GPT-6 Sol: Input $0.60 / Output $3.00 per 1M tokens; Claude Sonnet 5.5: Input $0.60 / Output $3.00 per 1M tokens. Rates depend on the billing unit, specification, and usage. Compare matching conditions in the model's detailed pricing; a single rate does not determine the total cost.
What are the key differences between GPT-6 Sol and Claude Sonnet 5.5?
GPT-6 Sol: Code
Sources
- Introducing GPT-6 Sol and Luna
- Using GPT-6 (model guidance)
- Introducing Claude Sonnet 5.5
- Claude Sonnet 5.5 model overview
Reviewed Oct 2, 2026