Claude Opus 5.5 vs GPT-6 Sol

Both shipped on the same day at adjacent tiers: whether Opus 5.5's depth is worth double GPT-6 Sol's price when their context windows are within five percent of each other.

What the numbers say

• GPT-6 Sol is about 2.0x cheaper on output tokens (120 vs 240 credits per 1M).
• GPT-6 Sol is the newer release (September 2026 vs September 2026).

Derived from the live registry Zeplik routes and bills against. Credits: 1 credit = $0.10, computed from the raw provider rate with a 1.20x margin.

Side by side

Try both on Zeplik

The honest answer to most model debates is to run your own prompt on both. Zeplik puts Claude Opus 5.5 and GPT-6 Sol in the same chat, so you can switch mid-conversation and compare answers on the work you actually do.

Frequently asked questions

What is the difference between Claude Opus 5.5 and GPT-6 Sol?

GPT-6 Sol is about 2.0x cheaper on output tokens (120 vs 240 credits per 1M). GPT-6 Sol is the newer release (September 2026 vs September 2026).

Is Claude Opus 5.5 or GPT-6 Sol cheaper?

GPT-6 Sol is cheaper: 120 credits per million output tokens against 240. 1 credit = $0.10, computed from the raw provider rate with a 1.20x margin.

Which has the larger context window, Claude Opus 5.5 or GPT-6 Sol?

GPT-6 Sol, at 1.1M tokens against 1M.

Can I use both Claude Opus 5.5 and GPT-6 Sol on Zeplik?

Yes. Zeplik is a multi-model chat, so both sit behind one account and you can switch between them mid-conversation to compare answers on your own prompt.

Do Claude Opus 5.5 and GPT-6 Sol need a paid plan?

Both need a paid plan (Plus or above). Usage is then billed in credits from your monthly allowance.

Related comparisons

• Claude Opus 5.5 vs Claude Opus 5The rare upgrade with nothing to weigh: Opus 5.5 is newer than Opus 5 and twenty percent cheaper on both input and output, at the same million-token window.
• GPT-6 Sol vs GPT-5.6 SolThe generational swap with no price to argue about: GPT-6 Sol replaces GPT-5.6 Sol at an identical $2 in and $10 out, with the same 1,050,000-token window.
• Claude Opus 5.5 vs GPT-6 AstraAnthropic's and OpenAI's deep-reasoning flagships, eighteen days apart -- and Astra asks two and a half times Opus 5.5's price for a window only five percent larger.
• GPT-6 Sol vs GPT-6 AstraThe upgrade decision inside the GPT-6 line: Astra costs five times Sol for the same 1,050,000-token window, so the question is which work is hard enough to need it.
• Claude Opus 5.5 vs Claude Sonnet 5The current Anthropic tier decision: Opus 5.5 costs twice Sonnet 5 for an identical million-token window, so the question is entirely about depth per turn.
• GPT-6 Sol vs GPT-6 LunaGPT-6's capability tier against its value tier, twenty times apart on both input and output price with the same context window on each.