High-volume, cost-sensitive work
Either one
Both cost $8.00 per million tokens on a typical mix of three input tokens for every output token.
Claude Opus 5.5 vs GPT-5.6 Sol: price, context and capabilities
Choose Claude Opus 5.5 for reused prompts and documents (RAG, agents), the hardest reasoning tasks, the latest release and the most recent knowledge; on the other points the two are level or the data is missing.
In short
- Both cost the same at the headline price ($8.00 / 1M tokens).
- GPT-5.6 Sol reads more per request: 1.05M tokens against 1M.
- Claude Opus 5.5 is the newer model (September 2026, against Jul 9, 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 Claude Opus 5.5
Claude Opus 5.5 charges $0.20 per million cached input tokens, against $0.40 for GPT-5.6 Sol.
Hardest reasoning tasks
Choose Claude Opus 5.5
Claude Opus 5.5 scores 57.6 on the Artificial Analysis Intelligence Index, against 47 for GPT-5.6 Sol.
Reasoning over long documents
Either one
They are practically level on Long-context reasoning (AA-LCR) (84.7% and 84%).
Latest release
Choose Claude Opus 5.5
Claude Opus 5.5 is the newer release (September 2026, against Jul 9, 2026 for GPT-5.6 Sol).
Most recent knowledge
Choose Claude Opus 5.5
Claude Opus 5.5 was trained on data up to June 2026, against February 2026 for GPT-5.6 Sol.
Monthly cost at three volumes
| Volume | Claude Opus 5.5 | GPT-5.6 Sol | Difference |
|---|---|---|---|
| Prototype: 1M input, 250K output tokens | $9.00 | $9.00 | = |
| Production: 20M input, 5M output tokens | $180.00 | $180.00 | = |
| Scale: 500M input, 100M output tokens | $4,000 | $4,000 | = |
Standard rates, without caching or batch discounts. Volumes are per month.
Specifications side by side
| Claude Opus 5.5 | GPT-5.6 Sol | |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Category | Language models | Language models |
| Status | Generally available | Generally available |
| Headline price | $8.00 / 1M tokens | $8.00 / 1M tokens |
| Input | $4.00 / 1M tokens | $4.00 / 1M tokens |
| Output | $20.00 / 1M tokens | $20.00 / 1M tokens |
| Cached input | $0.20 / 1M tokens | $0.40 / 1M tokens |
| Context window | 1M | 1.05M |
| Max output | 128k | 128k |
| Released | September 2026 | Jul 9, 2026 |
| Knowledge cutoff | June 2026 | February 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-opus-5-5 | gpt-5.6-sol |
Benchmarks side by side
Leader in bold.
| Benchmark | Claude Opus 5.5 | GPT-5.6 Sol |
|---|---|---|
| Intelligence Index | 57.6 | 47 |
| SciCode | 66.9% | 57.1% |
| Humanity's Last Exam | 61.4% | 49.5% |
| MMMU-Pro (visual reasoning) | 87.7% | 83.4% |
| Long-context reasoning (AA-LCR) | 84.7% | 84% |
| Terminal-Bench Hard | No data | 65.9% |
| GPQA Diamond | No data | 94.1% |
| IFBench (instruction following) | No data | 72.7% |
| τ²-Bench (agentic tool use) | No data | 85.1% |
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 Opus 5.5 or GPT-5.6 Sol?
Choose Claude Opus 5.5 for reused prompts and documents (RAG, agents), the hardest reasoning tasks, the latest release and the most recent knowledge; on the other points the two are level or the data is missing.
Which is cheaper, Claude Opus 5.5 or GPT-5.6 Sol?
Both cost the same at the headline price ($8.00 / 1M tokens).
Which has the larger context window, Claude Opus 5.5 or GPT-5.6 Sol?
GPT-5.6 Sol reads more per request: 1.05M tokens against 1M.
What is the difference between Claude Opus 5.5 and GPT-5.6 Sol?
Claude Opus 5.5 is made by Anthropic and GPT-5.6 Sol by OpenAI. Both cost the same at the headline price ($8.00 / 1M tokens). GPT-5.6 Sol reads more per request: 1.05M tokens against 1M. Claude Opus 5.5 is the newer model (September 2026, against Jul 9, 2026).
How much do Claude Opus 5.5 and GPT-5.6 Sol cost per month?
At 20 million input and 5 million output tokens a month, Claude Opus 5.5 costs $180.00 and GPT-5.6 Sol costs $180.00, at standard rates.
Which is newer, Claude Opus 5.5 or GPT-5.6 Sol?
Claude Opus 5.5 was released on September 2026 and GPT-5.6 Sol on Jul 9, 2026.