Claude Opus 5.5 vs GPT-6.1 Sol
In Endless, GPT-6.1 Sol costs less: 162 credits per 1M input tokens and 810 per 1M output tokens, against 324 credits per 1M input tokens and 1620 per 1M output tokens for Claude Opus 5.5. Claude Opus 5.5 is made by Anthropic, and GPT-6.1 Sol by OpenAI. Claude Opus 5.5 is available on the Hobby plan and up, and GPT-6.1 Sol on every plan.
| Detail | Claude Opus 5.5 | GPT-6.1 Sol |
|---|---|---|
| Maker | Anthropic | OpenAI |
| Type | Chat model | Chat model |
| Price | 324 credits per 1M input tokens · 1620 credits per 1M output tokens | 162 credits per 1M input tokens · 810 credits per 1M output tokens |
| Availability | Available on Hobby and above | Available on every plan |
| Context window | 1M tokens | 1.05M tokens |
| Max output | 128K tokens | 128K tokens |
| Inputs | Text, images | Text, images |
| Outputs | Text | Text |
| Added to Endless | Sep 22, 2026 | Sep 29, 2026 |
When to pick Claude Opus 5.5
- Codebase-wide migrations, refactors and audits
- Research reports with source-checked figures and quotes
- Excel models and presentations ready for executives
- Long agent runs that delegate work to subagents
When to pick GPT-6.1 Sol
- Debugging across a large repository over many steps
- Planning and carrying out multi-step coding tasks
- Reviewing long documents and drafting structured summaries
- Complex work where GPT-6 Astra is more than you need
Questions about Claude Opus 5.5 and GPT-6.1 Sol
- Which is cheaper in Endless, Claude Opus 5.5 or GPT-6.1 Sol?
- In Endless, GPT-6.1 Sol costs less: 162 credits per 1M input tokens and 810 per 1M output tokens, against 324 credits per 1M input tokens and 1620 per 1M output tokens for Claude Opus 5.5.
- Who makes Claude Opus 5.5 and GPT-6.1 Sol?
- Claude Opus 5.5 is made by Anthropic, and GPT-6.1 Sol by OpenAI.
- Which plan do I need for Claude Opus 5.5 and GPT-6.1 Sol?
- Claude Opus 5.5 is available on the Hobby plan and up, and GPT-6.1 Sol on every plan.
- Can I use Claude Opus 5.5 and GPT-6.1 Sol in the same workspace?
- Yes. Both are in Endless, so you can switch between them in chat and pay for both from one shared credit balance.
Use both in Endless
Claude Opus 5.5 and GPT-6.1 Sol sit in the same workspace. Pick either one in chat, ask both the same question and compare the answers. Your team pays for both from one shared credit balance.