Claude Sonnet 5.5 vs GPT-6.1 Sol
Pick two to four models to compare benchmark scores, prices, context windows and speed. The link updates as you pick, so you can share the exact comparison.
Cheapest blended
Claude Sonnet 5.5GPT-6.1 Sol
Tie at $4.00 / 1M tokens
Largest context
GPT-6.1 Sol
1.05M tokens
Fastest output
Claude Sonnet 5.5
139 tokens/s
Top benchmark
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No benchmark they share
Specifications
| Spec | Claude Sonnet 5.5Anthropic | GPT-6.1 SolOpenAI |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Released | 28 Sep 2026 | 29 Sep 2026 |
| Licence | Proprietary | Proprietary |
| Context window | 1M tokens | 1.05M tokens |
| Max output | 128K tokens | 128K tokens |
| Input / 1M | $2.00* | $2.00* |
| Output / 1M | $10.00 | $10.00 |
| Cached input / 1M | $0.20 | $0.10 |
| Speed | 139 tokens/s | 64 tokens/s |
| Input types | text, image | text, image |
| Best for | CodingAgentsLong context | CodingAgentsReasoning |
* Claude Sonnet 5.5: Same per-token price as Sonnet 5. Cache reads use the standard 0.1x multiplier ($0.20). Uses the newer tokenizer (about 30% more tokens than pre-Opus 4.7 models). Safety classifiers can refuse; since 24 Sep 2026 some pre-output refusal categories are billed. Minimum cacheable prompt: 512 tokens.
* GPT-6.1 Sol: Cache reads are 0.05x input (95% off), not the usual 0.1x. Cache writes 1.25x input. Batch and Flex: $1 / $5. Fast mode: $4 / $20. OpenAI says an Ultrafast option is coming 'in the coming days'; it is not on the pricing page yet. Data residency +10%.
Benchmark scores
Officially reported scores only. A model with no published score on a benchmark shows a line, not a zero.
Price per 1M tokens
Context window and speed
Notes
- Claude Sonnet 5.5
- Anthropic's current Sonnet model, described as the best combination of speed and intelligence and a faster, lower-cost complement to Claude Opus 5.5 for well-scoped everyday tasks.
- GPT-6.1 Sol
- An upgrade to GPT-6 Sol that OpenAI says nearly matches GPT-6 Astra on agentic coding, computer use and professional work at one-fifth of Astra's standard token prices.
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