WhichBot › Compare › Claude Opus 5.5 vs GPT-6.1 Sol
Last checked Oct 28, 2026 · plain English · no paid picks
Claude Opus 5.5 vs GPT-6.1 Sol
Short answer: neither wins at everything.
Pick Claude Opus 5.5 if you need the strongest Claude for long documents, writing and coding.
Pick GPT-6.1 Sol if you want OpenAI's current main model for paid ChatGPT plans and for developers.
Claude Opus 5.5 vs GPT-6.1 Sol side by side
| Claude Opus 5.5 | GPT-6.1 Sol | |
|---|---|---|
| What it is | Anthropic's top model | OpenAI's main model on paid ChatGPT plans |
| Made by | Anthropic | OpenAI |
| Price | Developer price: $4 in and $20 out per million tokens | Developer price: $2 in and $10 out per million tokens |
| Good at | Hector's pick for long documents and writing; Best for: long documents, writing, coding; Reads up to 1,000,000 tokens at once; Reads: text, image, PDFs | Reads up to 1,050,000 tokens at once; Reads: text, image, PDFs |
| Where it runs | Claude Pro/Max | ChatGPT Plus/Pro |
| Status | Current. Retirement not sooner than Sep 22, 2027. Fast mode (up to ~2.5x faster output, $8/$40 per million tokens) is open to all developer service users since Oct 15, 2026 | Current |
| Sources | platform.claude.com · claude.com · models.dev · platform.claude.com (2) · platform.claude.com (3) | chatgpt.com · models.dev |
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Questions people ask
Is Claude Opus 5.5 or GPT-6.1 Sol better?
It depends on what you do. Pick Claude Opus 5.5 if you need the strongest Claude for long documents, writing and coding. Pick GPT-6.1 Sol if you want OpenAI's current main model for paid ChatGPT plans and for developers.
How does WhichBot decide?
Hector uses a written rubric: everyday usefulness, cost and free plans, privacy, reliability, ease of use, availability and safety. Rankings are one input, not the answer.
Facts come from the companies' own pages, linked above, and were last checked Oct 28, 2026. Prices are US and can change. Picks are Hector's: no paid picks, sponsors always labeled, and no sponsorship from AI labs. Our policy.