Claude Sonnet 5.5 vs GPT-6.1 Sol
Claude Sonnet 5.5 and GPT-6.1 Sol are within three points on the Models at Work leaderboard, which we treat as a tie (84 vs 82). They cost about the same per million tokens ($4 vs $4 blended). On Artificial Analysis' independent Intelligence Index, Claude Sonnet 5.5 leads 56 to 52.
| Claude Sonnet 5.5 · Anthropic | GPT-6.1 Sol · OpenAI | |
|---|---|---|
| Leaderboard rank | #4 | #5 |
| Score (0–100) | 84 | 82 |
| Tier | Workhorse | Workhorse |
| Price per 1M tokens | $2 in · $10 out | $2 in · $10 out |
| Context window | 1M | 1M |
| Open weights | No | No |
| Artificial Analysis Intelligence Index | 56 | 52 |
| Humanity's Sixth Sense (Scale) | — | 46.6 |
| Best for | Production coding assistants, High-volume agents, Default model for most teams | OpenAI-standardised teams, Agents API and Decisions API, Cost-controlled reasoning |
Choose Claude Sonnet 5.5 if…
- you need production coding assistants
- you need high-volume agents
- you need default model for most teams
The value pick of the table: second on the index at a fifth of the Opus price, and the fastest of the top five.
Choose GPT-6.1 Sol if…
- you need openai-standardised teams
- you need agents api and decisions api
- you need cost-controlled reasoning
Near-Astra intelligence at a fifth of the price, which is OpenAI's own line and, for once, the index agrees.
What practitioners say
Claude Sonnet 5.5: Less discussed than its siblings because it just works; the October cache-read price cut to $0.10 per million was the news.
GPT-6.1 Sol: The launch thread's title did the arguing: 'near-Astra for a fifth of the price' drew 955 comments, most of them about routing.
Questions people ask
Which is better, Claude Sonnet 5.5 or GPT-6.1 Sol?
Claude Sonnet 5.5 and GPT-6.1 Sol are within three points on the Models at Work leaderboard, which we treat as a tie (84 vs 82). They cost about the same per million tokens ($4 vs $4 blended). On Artificial Analysis' independent Intelligence Index, Claude Sonnet 5.5 leads 56 to 52.
When should I choose Claude Sonnet 5.5 over GPT-6.1 Sol?
Choose Claude Sonnet 5.5 for production coding assistants, high-volume agents, default model for most teams. The value pick of the table: second on the index at a fifth of the Opus price, and the fastest of the top five.
When should I choose GPT-6.1 Sol over Claude Sonnet 5.5?
Choose GPT-6.1 Sol for openai-standardised teams, agents api and decisions api, cost-controlled reasoning. Near-Astra intelligence at a fifth of the price, which is OpenAI's own line and, for once, the index agrees.
Which is cheaper, Claude Sonnet 5.5 or GPT-6.1 Sol?
Claude Sonnet 5.5 costs $2 per million input tokens and $10 per million output tokens on Anthropic's list price (Claude pricing, read Oct 10, 2026). GPT-6.1 Sol costs $2 per million input tokens and $10 per million output tokens on OpenAI's list price (OpenAI API pricing, read Oct 10, 2026).
Scores come from the Models at Work leaderboard: Score is 0 to 100: 50% independent evals normalised within this table, 20% price-performance, 15% practitioner sentiment from Signals and community threads, 15% operational fit (context, speed, availability, open weights). Models within three points are a tie in practice. Vendor-published figures are labelled as such and never counted as independent. Prices are vendor list prices where published; blended figures assume three input tokens per output token.