High-volume, cost-sensitive work
Either one
Both cost $4.00 per million tokens on a typical mix of three input tokens for every output token.
Claude Sonnet 5 vs GPT-6.1 Sol: price, context and capabilities
Choose GPT-6.1 Sol for reused prompts and documents (RAG, agents), the hardest reasoning tasks and the latest release; on the other points the two are level or the data is missing.
In short
- Both cost the same at the headline price ($4.00 / 1M tokens).
- GPT-6.1 Sol reads more per request: 1.05M tokens against 1M.
- GPT-6.1 Sol is the newer model (Sep 29, 2026, against June 2026).
Which should you choose?
Each answer below comes straight from the published prices, specifications and independent benchmark results.
Reused prompts and documents (RAG, agents)
Choose GPT-6.1 Sol
GPT-6.1 Sol charges $0.10 per million cached input tokens, against $0.20 for Claude Sonnet 5.
Hardest reasoning tasks
Choose GPT-6.1 Sol
GPT-6.1 Sol scores 51.8 on the Artificial Analysis Intelligence Index, against 38.2 for Claude Sonnet 5.
Reasoning over long documents
Either one
They are practically level on Long-context reasoning (AA-LCR) (82% and 83%).
Latest release
Choose GPT-6.1 Sol
GPT-6.1 Sol is the newer release (Sep 29, 2026, against June 2026 for Claude Sonnet 5).
Monthly cost at three volumes
| Volume | Claude Sonnet 5 | GPT-6.1 Sol | Difference |
|---|---|---|---|
| Prototype: 1M input, 250K output tokens | $4.50 | $4.50 | = |
| Production: 20M input, 5M output tokens | $90.00 | $90.00 | = |
| Scale: 500M input, 100M output tokens | $2,000 | $2,000 | = |
Standard rates, without caching or batch discounts. Volumes are per month.
Specifications side by side
| Claude Sonnet 5 | GPT-6.1 Sol | |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Category | Language models | Language models |
| Status | Legacy | Generally available |
| Headline price | $4.00 / 1M tokens | $4.00 / 1M tokens |
| Input | $2.00 / 1M tokens | $2.00 / 1M tokens |
| Output | $10.00 / 1M tokens | $10.00 / 1M tokens |
| Cached input | $0.20 / 1M tokens | $0.10 / 1M tokens |
| Context window | 1M | 1.05M |
| Max output | 128k | 128k |
| Released | June 2026 | Sep 29, 2026 |
| Knowledge cutoff | No data | April 2026 |
| Licence | Proprietary | Proprietary |
| Capabilities | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API |
| API model id | claude-sonnet-5 | gpt-6.1-sol |
Benchmarks side by side
Leader in bold.
| Benchmark | Claude Sonnet 5 | GPT-6.1 Sol |
|---|---|---|
| Intelligence Index | 38.2 | 51.8 |
| SciCode | 54.3% | 54.2% |
| Humanity's Last Exam | 41.3% | 52.9% |
| MMMU-Pro (visual reasoning) | 77.3% | 86% |
| Long-context reasoning (AA-LCR) | 82% | 83% |
| GPQA Diamond | 91.1% | No data |
Independent evaluations by Artificial Analysis, run the same way for every model, at the reasoning setting shown. Percentages unless marked as an index.
Frequently asked questions
Should I choose Claude Sonnet 5 or GPT-6.1 Sol?
Choose GPT-6.1 Sol for reused prompts and documents (RAG, agents), the hardest reasoning tasks and the latest release; on the other points the two are level or the data is missing.
Which is cheaper, Claude Sonnet 5 or GPT-6.1 Sol?
Both cost the same at the headline price ($4.00 / 1M tokens).
Which has the larger context window, Claude Sonnet 5 or GPT-6.1 Sol?
GPT-6.1 Sol reads more per request: 1.05M tokens against 1M.
What is the difference between Claude Sonnet 5 and GPT-6.1 Sol?
Claude Sonnet 5 is made by Anthropic and GPT-6.1 Sol by OpenAI. Both cost the same at the headline price ($4.00 / 1M tokens). GPT-6.1 Sol reads more per request: 1.05M tokens against 1M. GPT-6.1 Sol is the newer model (Sep 29, 2026, against June 2026).
How much do Claude Sonnet 5 and GPT-6.1 Sol cost per month?
At 20 million input and 5 million output tokens a month, Claude Sonnet 5 costs $90.00 and GPT-6.1 Sol costs $90.00, at standard rates.
Which is newer, Claude Sonnet 5 or GPT-6.1 Sol?
GPT-6.1 Sol was released on Sep 29, 2026 and Claude Sonnet 5 on June 2026.