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GPT-5.2 Codex vs Kimi K2.6

GPT-5.2 Codex (2025) and Kimi K2.6 (2026) are agentic coding models from OpenAI and Moonshot AI. GPT-5.2 Codex ships a not-yet-sourced context window, while Kimi K2.6 ships a 262K-token context window. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing. The goal is to make the tradeoff clear before deeper testing.

Kimi K2.6 is safer overall; choose GPT-5.2 Codex when coding workflow support matters.

Decision scorecard

Local evidence first
SignalGPT-5.2 CodexKimi K2.6
Decision fitCoding, Agents, and VisionCoding, RAG, and Agents
Context window262K
Cheapest output-$3.5/1M tokens
Provider routes0 tracked4 tracked
Shared benchmarks0 rows0 rows

Decision tradeoffs

Choose GPT-5.2 Codex when...
  • GPT-5.2 Codex uniquely exposes Code execution in local model data.
  • Local decision data tags GPT-5.2 Codex for Coding, Agents, and Vision.
Choose Kimi K2.6 when...
  • Kimi K2.6 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Kimi K2.6 has broader tracked provider coverage for fallback and procurement flexibility.
  • Local decision data tags Kimi K2.6 for Coding, RAG, and Agents.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output prices on this page.

GPT-5.2 Codex

Unavailable

No complete token price in local provider data

Kimi K2.6

$1,475

Cheapest tracked route: OpenRouter

Cost delta unavailable until both models have sourced input and output token prices.

Switch friction

GPT-5.2 Codex -> Kimi K2.6
  • No overlapping tracked provider route is sourced for GPT-5.2 Codex and Kimi K2.6; plan for SDK, billing, or endpoint changes.
  • Check replacement coverage for Code execution before moving production traffic.
Kimi K2.6 -> GPT-5.2 Codex
  • No overlapping tracked provider route is sourced for Kimi K2.6 and GPT-5.2 Codex; plan for SDK, billing, or endpoint changes.
  • GPT-5.2 Codex adds Code execution in local capability data.

Specs

Specification
Released2025-12-182026-04-20
Context window262K
Parameters1T
Architecturedecoder onlyMixture of Experts (MoE)
LicenseProprietaryOpen Source
Knowledge cutoff--

Pricing and availability

Pricing attributeGPT-5.2 CodexKimi K2.6
Input price-$0.75/1M tokens
Output price-$3.5/1M tokens
Providers-

Capabilities

CapabilityGPT-5.2 CodexKimi K2.6
VisionYesYes
MultimodalYesYes
ReasoningYesYes
Function callingYesYes
Tool useYesYes
Structured outputsNoNo
Code executionYesNo

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on code execution: GPT-5.2 Codex. Both models share vision, multimodal input, reasoning mode, and function calling, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.

Pricing coverage is uneven: GPT-5.2 Codex has no token price sourced yet and Kimi K2.6 has $0.75/1M input tokens. Provider availability is 0 tracked routes versus 4. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose GPT-5.2 Codex when coding workflow support are central to the workload. Choose Kimi K2.6 when coding workflow support and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency. For teams standardizing a stack, that distinction is often the difference between a benchmark win and a reliable deployment.

FAQ

Is GPT-5.2 Codex or Kimi K2.6 open source?

GPT-5.2 Codex is listed under Proprietary. Kimi K2.6 is listed under Open Source. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.

Which is better for vision, GPT-5.2 Codex or Kimi K2.6?

Both GPT-5.2 Codex and Kimi K2.6 expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, GPT-5.2 Codex or Kimi K2.6?

Both GPT-5.2 Codex and Kimi K2.6 expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for reasoning mode, GPT-5.2 Codex or Kimi K2.6?

Both GPT-5.2 Codex and Kimi K2.6 expose reasoning mode. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for function calling, GPT-5.2 Codex or Kimi K2.6?

Both GPT-5.2 Codex and Kimi K2.6 expose function calling. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Where can I run GPT-5.2 Codex and Kimi K2.6?

GPT-5.2 Codex is available on the tracked providers still being sourced. Kimi K2.6 is available on NVIDIA NIM, Moonshot AI Kimi, Fireworks AI, and OpenRouter. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-05-11. Data sourced from public model cards and provider documentation.