# Claude Opus 5.5 vs GPT-6 Sol

URL: https://aistack.sh/compare/claude-opus-5-5-vs-gpt-6-sol
Last updated: 2026-09-24
Model pages: https://aistack.sh/model/claude-opus-5-5, https://aistack.sh/model/gpt-6-sol

## Quick answer

These are the two coding-agent defaults: Claude Opus 5.5 in Claude Code and GPT-6 Sol in Codex. Sol is half the price at $2 / $10 per 1M tokens against Opus 5.5's $4 / $20, so for API-metered agent work Sol is the cheaper default; if you are already paying for a Claude plan and working in Claude Code, Opus 5.5 is what you get without changing anything.

## Specs

| Spec | Claude Opus 5.5 | GPT-6 Sol |
| --- | --- | --- |
| Released | Sep 22, 2026 | Sep 22, 2026 |
| Status | Available | Rolling out |
| API model ID | claude-opus-5-5 | gpt-6-sol |
| API price (in / out) | $4 / $20 per 1M tokens | $2 / $10 per 1M tokens |
| Cache read | $0.20 per 1M tokens | $0.20 per 1M tokens |
| Context window | 1M tokens | 1.05M tokens |
| Plans | Pro, Max, Team, Enterprise | Plus, Pro, Business, Enterprise, Edu |
| Platforms | Claude API, Amazon Bedrock, Claude Platform on AWS, Google Cloud, Microsoft Foundry | OpenAI API |
| Runs in | Claude, Claude Code | Codex, ChatGPT |

"-" means the value could not be verified on a vendor page.

## FAQ

### Which is cheaper, Claude Opus 5.5 or GPT-6 Sol?

GPT-6 Sol, at $2 input and $10 output per 1M tokens (short-context rates), half of Claude Opus 5.5's $4 / $20.

### Are they both coding-agent defaults?

Yes. Claude Code defaults to Opus 5.5 on Pro, Max, Team, Enterprise and the API; OpenAI's changelog names GPT-6 Sol the Codex default, starting on the Sol Light preset.

### When were they released?

The same day, September 22, 2026.

### Which plans include them?

Opus 5.5 is on Claude Pro, Max, Team and Enterprise. GPT-6 Sol is rolling out to Plus, Pro, Business, Enterprise and Edu in Codex and ChatGPT Work.

## Also compared

- [Claude Fable 5.1 vs Claude Opus 5.5](https://aistack.sh/compare/claude-fable-5-1-vs-claude-opus-5-5)
- [Claude Opus 5.5 vs GPT-6 Astra](https://aistack.sh/compare/claude-opus-5-5-vs-gpt-6-astra)
- [GPT-6 Astra vs GPT-6 Sol](https://aistack.sh/compare/gpt-6-astra-vs-gpt-6-sol)

## Sources

- [Claude Developer Platform release notes](https://platform.claude.com/docs/en/release-notes/overview), read 2026-09-24
- [Claude API pricing](https://platform.claude.com/docs/en/about-claude/pricing), read 2026-09-24
- [Claude models overview](https://platform.claude.com/docs/en/about-claude/models/overview), read 2026-09-24
- [Claude Code model configuration](https://code.claude.com/docs/en/model-config), read 2026-09-24
- [Claude plans and pricing](https://claude.com/pricing), read 2026-09-24
- [Anthropic: Claude Opus 5.5 launch](https://www.anthropic.com/claude-opus-5-5), read 2026-09-24
- [OpenAI: ChatGPT Work and Codex changelog](https://learn.chatgpt.com/docs/changelog), read 2026-09-24
- [OpenAI: ChatGPT and Codex models](https://learn.chatgpt.com/docs/models), read 2026-09-24
- [OpenAI API models](https://developers.openai.com/api/docs/models), read 2026-09-24
- [OpenAI API pricing](https://developers.openai.com/api/docs/pricing), read 2026-09-24