GPT-5.6 Terra vs Kimi K3

GPT-5.6 Terra and Kimi K3 are both current production-tier models. GPT-5.6 Terra leads on vision.

Specs side by side

Metric
OpenAI
GPT-5.6 Terra
Z.ai
Kimi K3
Input price (per 1M)$2.5$3
Output price (per 1M)$15$15
Context window1.1M tokens1.0M tokens
Speed tierbalancedbalanced
Open weightsNoNo
EU regionYesNo
Free tierNoNo
Prompt cachingYesYes
Vision inputYesYes
Extended thinkingYesYes

When to choose each

OpenAI

Choose GPT-5.6 Terra if…

  • EU data residency is required
  • HIPAA eligibility is required
  • Vision is central to your workload
Z.ai

Choose Kimi K3 if…

  • Kimi K3 is in the same tier as GPT-5.6 Terra — pick by provider preference or API ecosystem

Benchmark delta

GPT-5.6 Terra leads on

  • Vision

Kimi K3 leads on

Kimi K3 has no meaningful benchmark lead in this pair.

FAQ — GPT-5.6 Terra vs Kimi K3

GPT-5.6 Terra vs Kimi K3 — which is better?

GPT-5.6 Terra and Kimi K3 are both current production-tier models. GPT-5.6 Terra leads on vision. The right pick depends on your use case — see "When to choose each" above for a data-driven decision.

How does GPT-5.6 Terra pricing compare to Kimi K3?

GPT-5.6 Terra costs $2.5 / $15 per 1M vs Kimi K3 at $3 / $15 per 1M. Kimi K3 is cheaper on input tokens by roughly 0%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.

Does GPT-5.6 Terra or Kimi K3 have the bigger context window?

GPT-5.6 Terra has a 1.1M-token context window — 1× the 1.0M context of Kimi K3. Enough for entire codebases, books, or multi-document RAG.

Is there a free tier for GPT-5.6 Terra or Kimi K3?

GPT-5.6 Terra: no — Free $5 credit for new accounts; paid thereafter. Kimi K3: no — No free API tier; kimi.com web chat is free with limits.

Which is better for coding — GPT-5.6 Terra or Kimi K3?

Kimi K3 leads on coding benchmarks (GPT-5.6 Terra: 93/100, Kimi K3: 95/100). For production coding agents also weigh tool-use performance — GPT-5.6 Terra scores 93, Kimi K3 scores 90.