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 19.8 pts. On pricing, GLM-5 costs $0.72/1M input tokens versus $0.95/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing.
GLM-5.1 is safer overall; choose GLM-5 when provider fit matters.
Specs
Pricing and availability
| GLM-5 | GLM-5.1 | |
|---|---|---|
| Input price | $0.72/1M tokens | $0.95/1M tokens |
| Output price | $2.3/1M tokens | $3.15/1M tokens |
| Providers |
Capabilities
| GLM-5 | GLM-5.1 | |
|---|---|---|
| Vision | ||
| Multimodal | ||
| Reasoning | ||
| Function calling | ||
| Tool use | ||
| Structured outputs | ||
| Code execution |
Benchmarks
| Benchmark | GLM-5 | GLM-5.1 |
|---|---|---|
| SWE-bench Pro | 38.6 | 58.4 |
Deep dive
On shared benchmark coverage, SWE-bench Pro has GLM-5 at 38.6 and GLM-5.1 at 58.4, with GLM-5.1 ahead by 19.8 points. The largest visible gap is 19.8 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 $0.72/1M input and $2.3/1M output tokens, while GLM-5.1 lists $0.95/1M input and $3.15/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts GLM-5 lower by about $0.42 per million blended tokens. Availability is 5 providers versus 2, 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 $0.72/1M input and $2.3/1M output tokens. GLM-5.1 costs $0.95/1M input and $3.15/1M 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 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 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 and OpenRouter. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-04-24. Data sourced from public model cards and provider documentation.