By the toolist.ai editors. Researched from public sources, not hands-on tested by toolist.ai. Updated October 13, 2026; prices checked October 13, 2026.
GPT-6.1 Sol vs Claude Sonnet 5.5
Verdict
At the same token prices ($2 in, $10 out and $0.10 cached per million), Claude Sonnet 5.5 is the stronger pick on published benchmarks. It scores higher on six of the eight Artificial Analysis benchmarks both have, with its biggest leads on the Coding Agent Index (68.4 against 60.1) and GDPval-AA (1838 against 1592 Elo). GPT-6.1 Sol wins the Intelligence Index at each model's default effort (47.8 against 46.8) and Terminal-Bench-Science, returns its first token sooner and offers paid Fast and Ultrafast modes.
Verdict based on published prices, limits and benchmarks, not on our own tests.
Choose GPT-6.1 Sol if
- You want a fast first token at the default effort (7.6 seconds against 14.6)
- You need a paid speed tier (Fast mode at double the standard price, Ultrafast at six times)
- Your work is scientific terminal work (58.1% against 53.3% on Terminal-Bench-Science)
- You already pay for ChatGPT Plus or use Codex, which include GPT-6.1 Sol
Choose Claude Sonnet 5.5 if
- You run coding agents (68.4 against 60.1 on the Coding Agent Index; 63.6% against 56.1% on Terminal-Bench 4.0)
- Your work is knowledge work (1838 against 1592 Elo on GDPval-AA)
- Your prompts often pass 272,000 tokens, where OpenAI charges GPT-6.1 Sol twice the input rate and 1.5 times the output rate, and Anthropic adds no surcharge
- You want faster output (96.8 tokens a second at high effort against 55.2 at medium)
Price
Input costs the same on both. Output costs the same on both.
| Per million tokens | GPT-6.1 Sol | Claude Sonnet 5.5 |
|---|---|---|
| Input | $2 source | $2 source |
| Cached input | $0.10 source | $0.10 source |
| Output | $10 source | $10 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 and Ultrafast six times.
Claude Sonnet 5.5: Cache writes cost $2.50 per million tokens (5-minute cache) or $4 (1-hour cache). The Batch API costs half. There is no long-context surcharge and no fast mode.
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 Sonnet 5.5 |
|---|---|---|
| Support chatbot 100,000 replies, each 3,000 input and 400 output tokens, no caching (300M in, 40M out) | $1,000 | $1,000 |
| 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 | $127 |
| Coding agent 200 tasks, each 1.5 million input tokens (90% cache hits) and 50,000 output tokens (300M in, 10M out) | $187 | $187 |
Price your own workload
| Model | Cost a month |
|---|---|
| GPT-6.1 Sol | $150 |
| Claude Sonnet 5.5 | $150 |
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 Sonnet 5.5 | |
|---|---|---|
| Released | September 29, 2026 source | September 28, 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-sonnet-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 Sonnet 5.5 |
|---|---|---|
| Artificial Analysis Intelligence Index max effort | 51.8 source | 56.0 source |
| Intelligence Index at everyday effort | 47.8 (medium effort, the API default) source | 46.8 (high effort, the API default) source |
| Coding Agent Index | 60.1 (Codex harness, max effort) source | 68.4 (Claude Code harness, max effort) source |
| Terminal-Bench 4.0 max effort | 56.1% source | 63.6% source |
| Humanity's Last Exam max effort | 52.9% source | 55.0% source |
| GDPval-AA v2.1 (Elo) max effort | 1592 source | 1838 source |
| SciCode max effort | 54.2% source | 61.0% source |
| Terminal-Bench-Science 0.1 max effort | 58.1% source | 53.3% source |
| Output speed | 55.2 tokens/s (medium effort, OpenAI API) source | 96.8 tokens/s (high 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 Sonnet 5.5: price, context window and benchmarks
- Claude Haiku 5.5 vs Claude Sonnet 5.5
- Claude Opus 5.5 vs Claude Sonnet 5.5
- GPT-6.1 Sol vs Claude Opus 5.5
- 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 2026-10-13)
- OpenAI API docs: Pricing (checked 2026-10-13)
- OpenAI API docs: Changelog (checked 2026-10-13)
- OpenAI API docs: Reasoning models (checked 2026-10-13)
- OpenAI API docs: GPT-6.1 Sol vs GPT-6 Sol (checked 2026-10-13)
- ChatGPT docs: Models (checked 2026-10-13)
- Artificial Analysis: GPT-6.1 Sol (max) (checked 2026-10-13)
- Artificial Analysis: GPT-6.1 Sol (medium) (checked 2026-10-13)
- Artificial Analysis: GPT-6.1 Sol vs GPT-6 Astra (checked 2026-10-13)
- Artificial Analysis: Coding agents (checked 2026-10-13)
- OpenRouter: GPT-6.1 Sol (checked 2026-10-13)
- Anthropic: Introducing Claude Sonnet 5.5 (checked 2026-10-13)
- Claude docs: Claude Sonnet 5.5 (checked 2026-10-13)
- Claude docs: What's new in Claude Sonnet 5.5 (checked 2026-10-13)
- Claude docs: Pricing (checked 2026-10-13)
- Claude plans and pricing (checked 2026-10-13)
- Claude docs: API and data retention (checked 2026-10-13)
- Artificial Analysis: Claude Sonnet 5.5 (max) (checked 2026-10-13)
- Artificial Analysis: Claude Sonnet 5.5 (high) (checked 2026-10-13)
- OpenRouter: Claude Sonnet 5.5 (checked 2026-10-13)