LLM Reference

GLM-5.1 vs Kimi K2.5

GLM-5.1 (2026) and Kimi K2.5 (2026) compare a standalone API model against a coding-specialized model. GLM-5.1 ships a 200k-token context window, while Kimi K2.5 ships a 256k-token context window. On Google-Proof Q&A, Kimi K2.5 leads by 1.7 pts. On pricing, Kimi K2.5 costs $0.44/1M input tokens versus $0.98/1M for the alternative. This page treats the result as workflow and deployment fit, not a universal model winner.

Treat this as a product-type comparison: GLM-5.1 is standalone API model, while Kimi K2.5 is coding-specialized model. Choose based on workflow fit before reading any benchmark or price row as decisive.

Decision scorecard

Local evidence first
SignalGLM-5.1Kimi K2.5
Product typeStandalone API modelCoding-specialized model
Best forreasoning-heavy apps, tool-calling agents, and provider-routed productioncustom coding agents, code generation, and tool loops
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window200k256k
Cheapest output$3.08/1M tokens$2/1M tokens
Provider routes5 tracked10 tracked
Shared benchmarks6 rowsGoogle-Proof Q&A leader

Decision tradeoffs

Choose GLM-5.1 when...
  • GLM-5.1 holds a shared-benchmark lead on MCP-Atlas, ahead by 42.3 points.
  • GLM-5.1 uniquely exposes Reasoning, Tool use, and Code execution in local model data.
  • Local decision data tags GLM-5.1 for Coding, RAG, and Agents.
Choose Kimi K2.5 when...
  • Kimi K2.5 holds a shared-benchmark lead on Google-Proof Q&A, ahead by 1.7 points.
  • Kimi K2.5 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Kimi K2.5 has the lower cheapest tracked output price at $2/1M tokens.
  • Kimi K2.5 has broader tracked provider coverage for fallback and procurement flexibility.
  • Kimi K2.5 uniquely exposes Vision and Multimodal in local model data.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate Kimi K2.5

GLM-5.1

$1,554

Cheapest tracked route/tier: Z.ai

Kimi K2.5

$852

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $702. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

GLM-5.1 -> Kimi K2.5
  • Provider overlap exists on Fireworks AI, OpenRouter, and Vercel AI Gateway; start route-level A/B tests there.
  • Kimi K2.5 is $1.08/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Reasoning, Tool use, and Code execution before moving production traffic.
  • Kimi K2.5 adds Vision and Multimodal in local capability data.
Kimi K2.5 -> GLM-5.1
  • Provider overlap exists on OpenRouter, Fireworks AI, and Vercel AI Gateway; start route-level A/B tests there.
  • GLM-5.1 is $1.08/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Check replacement coverage for Vision and Multimodal before moving production traffic.
  • GLM-5.1 adds Reasoning, Tool use, and Code execution in local capability data.

Specs

Specification
Released2026-04-072026-03-15
Context window200k256k
Parameters754B total, 40B active1T (MoE, 384 experts)
Architecturemixture of expertsmixture of experts
LicenseMIT(OSI)Proprietary
OpennessOpen sourceProprietary
Commercial useCommercial use allowedCommercial use with conditions
Knowledge cutoff2025-11-

Pricing and availability

Pricing attributeGLM-5.1Kimi K2.5
Input price$0.98/1M tokens$0.44/1M tokens
Output price$3.08/1M tokens$2/1M tokens
Providers

Capabilities

CapabilityGLM-5.1Kimi K2.5
VisionNoYes
MultimodalNoYes
ReasoningYesNo
Function callingYesYes
Tool useYesNo
Structured outputsYesYes
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkGLM-5.1Kimi K2.5
Google-Proof Q&A86.287.9
AIME 202595.396.1
Humanity's Last Exam31.050.2
MCP-Atlas71.829.5
Terminal-Bench 2.063.550.8
SWE-rebench62.758.5

Deep dive

On shared benchmark coverage, Google-Proof Q&A has GLM-5.1 at 86.2 and Kimi K2.5 at 87.9, with Kimi K2.5 ahead by 1.7 points; AIME 2025 has GLM-5.1 at 95.3 and Kimi K2.5 at 96.1, with Kimi K2.5 ahead by 0.8 points; Humanity's Last Exam has GLM-5.1 at 31 and Kimi K2.5 at 50.2, with Kimi K2.5 ahead by 19.2 points. The largest visible gap is 19.2 points on Humanity's Last Exam, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.

The capability footprint differs most on vision: Kimi K2.5, multimodal input: Kimi K2.5, reasoning mode: GLM-5.1, tool use: GLM-5.1, and code execution: GLM-5.1. Both models share function calling and structured outputs, 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.

For cost, GLM-5.1 lists $0.98/1M input and $3.08/1M output tokens on the cheapest tracked provider, while Kimi K2.5 lists $0.44/1M input and $2/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Kimi K2.5 lower by about $0.70 per million blended tokens. Availability is 5 providers versus 10, so concentration risk also matters.

Choose GLM-5.1 when coding workflow support are central to the workload. Choose Kimi K2.5 when coding workflow support, larger context windows, and lower input-token cost are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.

FAQ

Which has a larger context window, GLM-5.1 or Kimi K2.5?

Kimi K2.5 supports 256k tokens, while GLM-5.1 supports 200k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is cheaper, GLM-5.1 or Kimi K2.5?

Kimi K2.5 is cheaper on tracked token pricing. GLM-5.1 costs $0.98/1M input and $3.08/1M output tokens. Kimi K2.5 costs $0.44/1M input and $2/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is GLM-5.1 or Kimi K2.5 open source?

GLM-5.1 is listed under MIT. Kimi K2.5 is listed under Proprietary. 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, GLM-5.1 or Kimi K2.5?

Kimi K2.5 has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, GLM-5.1 or Kimi K2.5?

Kimi K2.5 has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run GLM-5.1 and Kimi K2.5?

GLM-5.1 is available on Z.ai, OpenRouter, Fireworks AI, Vercel AI Gateway, and Novita AI. Kimi K2.5 is available on Cloudflare Workers AI, Fireworks AI, OpenRouter, Together AI, and NVIDIA NIM. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-04. Data sourced from public model cards and provider documentation.