By the toolist.ai editors. Researched from public sources, not hands-on tested by toolist.ai. Updated October 6, 2026; prices checked October 6, 2026.
GPT-6.1 Sol vs Claude Opus 5.5
Verdict
Claude Opus 5.5 is the stronger model: it scores higher on all eight benchmarks both have, from the Intelligence Index (57.6 against 51.8) to the Coding Agent Index (66.0 against 60.1). GPT-6.1 Sol costs half as much per token ($2 and $10 against $4 and $20), so it wins when volume and budget come first.
Verdict based on published prices, limits and benchmarks, not on our own tests.
Choose GPT-6.1 Sol if
- Budget comes first: our support-chatbot workload costs $1,000 a month on Sol against $2,000 on Opus 5.5
- You want a fast first token at the default effort (6.2 seconds against 20.6)
- Your prompts repeat: Sol's cached input costs $0.10 per million tokens against Opus 5.5's $0.20
Choose Claude Opus 5.5 if
- You want the strongest coding agent of the two (66.0 against 60.1 on the Coding Agent Index)
- Your work is knowledge work or research (1866 against 1575 Elo on GDPval-AA; 61.4% against 52.9% on Humanity's Last Exam)
- Your prompts run past 272,000 tokens, where OpenAI doubles Sol's input price and Anthropic adds no surcharge
Price
Input costs 2 times as much on Claude Opus 5.5 as on GPT-6.1 Sol. Output costs 2 times as much on Claude Opus 5.5 as on GPT-6.1 Sol.
| Per million tokens | GPT-6.1 Sol | Claude Opus 5.5 |
|---|---|---|
| Input | $2 source | $4 source |
| Cached input | $0.10 source | $0.20 source |
| Output | $10 source | $20 source |
GPT-6.1 Sol: Prompts over 272,000 input tokens are billed at twice the input rate and 1.5 times the output rate for the whole request. Batch and Flex processing cost half; Fast mode costs double.
Claude Opus 5.5: Cache writes cost $5 per million tokens (5-minute cache) or $8 (1-hour cache). The Batch API costs half. There is no long-context surcharge. Fast mode costs $8 in and $40 out.
Worked example: what a month costs
We priced three monthly workloads at the standard rates. The provider does not publish these figures.
| Workload | GPT-6.1 Sol | Claude Opus 5.5 |
|---|---|---|
| Support chatbot 100,000 replies, each 3,000 input and 400 output tokens, no caching (300M in, 40M out) | $1,000 | $2,000 |
| Document Q&A 5,000 questions over the same 60,000-token document set (90% cache hits), 800 output tokens each (300M in, 4M out) | $127 | $254 |
| Coding agent 200 tasks, each 1.5 million input tokens (90% cache hits) and 50,000 output tokens (300M in, 10M out) | $187 | $374 |
Price your own workload
| Model | Cost a month |
|---|---|
| GPT-6.1 Sol | $150 |
| Claude Opus 5.5 | $300 |
Standard API prices, no batch or priority discounts. Cached input is billed at the cache-read price; cache-write charges are not included. Reasoning models bill their thinking as output tokens.
Limits and release dates
| GPT-6.1 Sol | Claude Opus 5.5 | |
|---|---|---|
| Released | September 29, 2026 source | September 22, 2026 source |
| Context window | 1,050,000 tokens source | 1,000,000 tokens source |
| Maximum output | 128,000 tokens source | 128,000 tokens source |
| Knowledge cutoff | April 30, 2026 source | June 2026 source |
| Input and output | Text and images in; text out source | Text and images in; text out source |
| API model name | gpt-6.1-sol | claude-opus-5-5 |
Benchmarks
Scores as published by the provider or measured by Artificial Analysis; higher is better. A dash means no score was published.
| Benchmark | GPT-6.1 Sol | Claude Opus 5.5 |
|---|---|---|
| Artificial Analysis Intelligence Index max effort | 51.8 source | 57.6 source |
| Intelligence Index at everyday effort medium effort, the API default | 47.8 source | 51.2 source |
| Coding Agent Index | 60.1 (Codex harness, max effort) source | 66.0 (Claude Code harness, max effort) source |
| Terminal-Bench 4.0 max effort | 56.1% source | 59.6% source |
| Humanity's Last Exam max effort | 52.9% source | 61.4% source |
| GDPval-AA v2.1 (Elo) max effort | 1575 source | 1866 source |
| SciCode max effort | 54.2% source | 66.9% source |
| Terminal-Bench-Science 0.1 max effort | 58.1% source | 59.0% source |
| Output speed | 48.8 tokens/s (medium effort, OpenAI API) source | 79.2 tokens/s (medium effort, Anthropic API) source |
Benchmark and speed data from Artificial Analysis where linked.
Read more
- GPT-6.1 Sol: price, context window and benchmarks
- Claude Opus 5.5: price, context window and benchmarks
- Claude Opus 5.5 vs Claude Fable 5.1
- Claude Opus 5.5 vs GPT-6 Astra
- GPT-6.1 Sol vs GPT-6 Astra
- GPT-6.1 Sol vs GPT-6 Sol
- AI model API price table
Sources
- OpenAI API docs: GPT-6.1 Sol (checked 2026-10-06)
- OpenAI API docs: Pricing (checked 2026-10-06)
- OpenAI API docs: Changelog (checked 2026-10-06)
- OpenAI API docs: Reasoning models (checked 2026-10-06)
- OpenAI API docs: GPT-6.1 Sol vs GPT-6 Sol (checked 2026-10-06)
- ChatGPT docs: Models (checked 2026-10-06)
- Artificial Analysis: GPT-6.1 Sol (max) (checked 2026-10-06)
- Artificial Analysis: GPT-6.1 Sol (medium) (checked 2026-10-06)
- Artificial Analysis: GPT-6.1 Sol vs GPT-6 Astra (checked 2026-10-06)
- Artificial Analysis: Coding agents (checked 2026-10-06)
- OpenRouter: GPT-6.1 Sol (checked 2026-10-06)
- Anthropic: Introducing Claude Opus 5.5 (checked 2026-10-06)
- Claude docs: Claude Opus 5.5 (checked 2026-10-06)
- Claude docs: What's new in Claude Opus 5.5 (checked 2026-10-06)
- Claude docs: Pricing (checked 2026-10-06)
- Claude plans and pricing (checked 2026-10-06)
- Claude docs: API and data retention (checked 2026-10-06)
- Artificial Analysis: Claude Opus 5.5 (max) (checked 2026-10-06)
- Artificial Analysis: Claude Opus 5.5 (medium) (checked 2026-10-06)
- OpenRouter: Claude Opus 5.5 (checked 2026-10-06)