Claude Opus vs GPT Sol
Two mid-frontier models, now that GPT-6 Astra sits above Sol and Claude Fable 5.1 sits above Opus. Sol is the broader generalist; Opus 5.5 leads on agentic and coding work and is the model Anthropic itself tells you to start with. At $4 and $20 per million tokens, Opus 5.5 costs twice as much as Sol's $2 and $10, so the deciding factor is whether that agentic edge justifies double the bill.
| Claude Opus | GPT Sol | |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Current release | Opus 5.5 | GPT-6.1 Sol |
| Tier | Frontier | Frontier |
| Context | 1M | 1M |
| Cost | Premium | Moderate |
| Modalities | text, vision | text, vision |
| Open weights | No | No |
Cost is a tier, not a quote, providers change prices often. Check Anthropic and OpenAI before you commit. Last updated 2026-10-21.
Which one to pick
Claude OpusAnthropic · Opus 5.5
Agentic coding and multi-step engineering work, near the ceiling at a fraction of the price
Reach for it when- Multi-step agentic coding where the model runs for a long time without supervision
- Large refactors that must respect an existing codebase's conventions
- You want reasoning-effort control to trade cost against depth
GPT SolOpenAI · GPT-6.1 Sol
Frontier-grade generalist work now that Astra has taken the top of the line
Reach for it when- You are already deep in OpenAI tooling and want the least migration friction
- Half the token cost on the same class of work
- General knowledge and scientific work rather than shipping code
Related comparisons
- Claude Opus vs GPT AstraThe practical version of the frontier question, because Opus 5.5 costs well under half what Astra does, $4 and $20 per million tokens against $10 and $50, and Anthropic recommends it as the default for most workloads.
- GPT Astra vs GPT SolThe within-OpenAI upgrade question.
- Claude Opus vs Gemini ProTwo different bets.
- GPT Sol vs Gemini ProSol is the stronger all-round generalist; Gemini 3.1 Pro is the reasoning-benchmark leader at a comparable price, $2 and $12 against Sol's $2 and $10.
- Claude Opus vs GrokBoth are pitched at agentic coding.
- GPT Sol vs GrokSol is the safer default and scores higher overall; Grok 4.7 matches it on some agentic work at lower output cost, $2 and $6 against $2 and $10.