Head to head

GPT-5.6 Sol vs Kimi K2.6

GPT-5.6 Sol (OpenAI) and Kimi K2.6 (Moonshot AI) compared on intelligence, speed, context, and price — and which to choose. Both run on just4o.chat from one chat.

MetricGPT-5.6 SolKimi K2.6
Intelligence (AA index)43
Output speed (tokens/sec)58.7
Context window1.1M256K
Max output128K262K
Input price / 1M$5$0.95
Output price / 1M$30$4
Released2026-07-092026-04

Choose GPT-5.6 Sol if you want…

  • Larger context window (1.1M)

Choose Kimi K2.6 if you want…

  • Lower price ($1.71 / 1M blended)

Kimi K2.6

Kimi K2.6 is Moonshot AI's open-weight coding specialist built for the kind of work that takes hours, not seconds. Its signature capability is agent swarm orchestration — coordinating up to 300 sub-agents across 4,000 execution steps — enabling autonomous refactoring sessions that developers have run for over 13 hours straight. On SWE-Bench Verified it scores 80.2%, and it edges out GPT-5.4 on SWE-Bench Pro at 58.6%, making it the strongest open-weight coding model available at its price point. Users report up to 88% cost savings on coding workloads compared to proprietary alternatives, which is the real draw for teams running code-heavy pipelines at scale. The tradeoff is speed and occasional drift: at 40.6 tokens per second — well below the category median — it is not suited to real-time use. In long-running agentic tasks, users note the model can wander into unnecessary redesigns around the three-hour mark, requiring clear, constrained prompting to keep it on track. For deep, non-interactive coding work where cost efficiency and open-weight flexibility matter more than instant responses, K2.6 occupies a position few models can match.

Full Kimi K2.6 details →

FAQ

Which is better, GPT-5.6 Sol or Kimi K2.6?

GPT-5.6 Sol leads on 1 of the headline metrics (larger context window (1.1m)), while Kimi K2.6 wins on lower price ($1.71 / 1m blended). The right pick depends on whether you prioritise capability, speed, or cost.

Is GPT-5.6 Sol or Kimi K2.6 cheaper?

Kimi K2.6 is cheaper at $1.71 per 1M tokens (blended), versus $11.25.

Can I use both GPT-5.6 Sol and Kimi K2.6?

Yes. Both are available on just4o.chat from a single chat — you can switch between them per message with no separate subscriptions.