LLM Reference

GLM-5 vs GLM-5.1

GLM-5 (2026) and GLM-5.1 (2026) are frontier-tier reasoning models from Zhipu AI. GLM-5 ships a 200k-token context window, while GLM-5.1 ships a 200k-token context window. On SWE-bench Pro, GLM-5.1 leads by 3.3 pts. On pricing, GLM-5 costs $0.60/1M input tokens versus $1.05/1M for the alternative. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

GLM-5 is ~75% cheaper at $0.60/1M; pay for GLM-5.1 only for coding workflow support.

Decision scorecard

Local evidence first
SignalGLM-5GLM-5.1
Best forreasoning-heavy apps, tool-calling agents, and provider-routed productionreasoning-heavy apps, tool-calling agents, and provider-routed production
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window200k200k
Cheapest output$2.08/1M tokens$3.50/1M tokens
Provider routes7 tracked5 tracked
Shared benchmarks5 sharedSWE-bench Pro leader

Decision tradeoffs

Choose GLM-5 when...
  • GLM-5 holds a shared-benchmark lead on SWE-rebench, ahead by 0.1 points.
  • GLM-5 has the lower cheapest tracked output price at $2.08/1M tokens.
  • GLM-5 has broader tracked provider coverage for fallback and procurement flexibility.
  • Local decision data tags GLM-5 for Coding, RAG, and Agents.
Choose GLM-5.1 when...
  • GLM-5.1 holds a shared-benchmark lead on SWE-bench Pro, ahead by 3.3 points.
  • GLM-5.1 uniquely exposes Code execution in local model data.
  • Local decision data tags GLM-5.1 for Coding, RAG, and Agents.

Monthly cost at traffic

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

Lower estimate GLM-5

GLM-5

$1,000

Cheapest tracked route/tier: OpenRouter

GLM-5.1

$1,715

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $715. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

GLM-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 $1.42/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • GLM-5.1 adds Code execution in local capability data.
GLM-5.1 -> GLM-5
  • Provider overlap exists on Fireworks AI, OpenRouter, and Vercel AI Gateway; start route-level A/B tests there.
  • GLM-5 is $1.42/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Code execution before moving production traffic.

Specs

Specification
Released2026-02-112026-04-07
Context window200k200k
Parameters744B total, 40B active754B total, 40B active
ArchitectureMixture of ExpertsMixture of Experts
LicenseMITOSI-approvedMITOSI-approved
OpennessOpen sourceOpen source
WeightsAvailableAvailable
CodeUnknownUnknown
Commercial useCommercial use: permittedCommercial use: permitted
Knowledge cutoff2025-112025-11

Pricing and availability

Pricing attributeGLM-5GLM-5.1
Input price$0.60/1M tokens$1.05/1M tokens
Output price$2.08/1M tokens$3.50/1M tokens
Providers

Capabilities

CapabilityGLM-5GLM-5.1
VisionNoNo
MultimodalNoNo
ReasoningYesYes
Function callingYesYes
Tool useYesYes
Structured outputsYesYes
Code executionNoYes
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkGLM-5GLM-5.1
SWE-bench Pro55.158.4
Google-Proof Q&A86.086.2
AIME 202592.795.3
Humanity's Last Exam30.531.0
SWE-rebench62.862.7

Deep dive

On shared benchmark coverage, SWE-bench Pro has GLM-5 at 55.1 and GLM-5.1 at 58.4, with GLM-5.1 ahead by 3.3 points; Google-Proof Q&A has GLM-5 at 86 and GLM-5.1 at 86.2, with GLM-5.1 ahead by 0.2 points; AIME 2025 has GLM-5 at 92.7 and GLM-5.1 at 95.3, with GLM-5.1 ahead by 2.6 points. The largest visible gap is 3.3 points on SWE-bench Pro, 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 code execution: GLM-5.1. Both models share reasoning mode, function calling, tool use, 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 lists $0.60/1M input and $2.08/1M output tokens on the cheapest tracked provider, while GLM-5.1 lists $1.05/1M input and $3.50/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts GLM-5 lower by about $0.74 per million blended tokens. Availability is 7 providers versus 5, so concentration risk also matters.

Choose GLM-5 when provider fit, lower input-token cost, and broader provider choice are central to the workload. Choose GLM-5.1 when coding workflow support 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 or GLM-5.1?

GLM-5 supports 200k 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 or GLM-5.1?

GLM-5 is cheaper on tracked token pricing. GLM-5 costs $0.60/1M input and $2.08/1M output tokens. GLM-5.1 costs $1.05/1M input and $3.50/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is GLM-5 or GLM-5.1 open source?

GLM-5 is listed under MIT. GLM-5.1 is listed under MIT. 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 reasoning mode, GLM-5 or GLM-5.1?

Both GLM-5 and GLM-5.1 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, GLM-5 or GLM-5.1?

Both GLM-5 and GLM-5.1 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 GLM-5 and GLM-5.1?

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

Continue comparing

Last reviewed: 2026-06-30. Data sourced from public model cards and provider documentation.