Z.ai: GLM 5.1
Analysis Summary
GLM 5.1 is Z.ai's previous-generation flagship, with an intelligence index of 40.2, a coding index of 55.8, and an agentic index of 70.4 that places it fourteenth globally. Tool use and function calling are supported, and instruction following is strong. The 202K context window is adequate for most business tasks.
For businesses, GLM 5.1 is a capable choice for coding assistance and agentic workflows. Its agentic score is competitive with models costing significantly more. The absence of vision support limits its use in multimodal pipelines, and the context window is smaller than the 1M offered by some rivals. A newer sibling, GLM 5.2, has since been released with higher scores across all dimensions.
At $0.975 input and $4.30 output per million tokens, pricing is reasonable for its capability tier. Teams already evaluating Z.ai models should consider whether GLM 5.2 better fits their needs, but GLM 5.1 remains a strong performer for text-based agentic and coding tasks.
Assessed June 30, 2026
Editorial notes
GLM 5.1 from Z.ai combines a strong coding index of 55.8 and agentic index of 70.4 with competitive pricing, though it lacks vision and has a smaller context window than top-tier rivals.
Rankings consider pricing, capabilities, benchmarks, and real-world applicability and are refreshed as new models launch. Feedback?
Performance Profile
How Z.ai: GLM 5.1 compares
Z.ai: GLM 5.1 ranks #29 of 387 AI models we track for overall intelligence, #29 of 152 for coding, #14 of 294 for agentic tasks. Its 203K-token context window is larger than 65% of the models we list. At $0.97 per million input tokens it is cheaper than 26% of comparable models.
About Z.ai: GLM 5.1
GLM-5.1 delivers a major leap in coding capability, with particularly significant gains in handling long-horizon tasks. Unlike previous models built around minute-level interactions, GLM-5.1 can work independently and continuously on..
Capabilities
Performance Indices
Source: Artificial Analysis
Benchmark Scores
Intelligence
Technical
Content
Benchmark data from Artificial Analysis and Hugging Face
How does Z.ai: GLM 5.1 stack up?
Compare side-by-side with other professional models.
Model Information
| OpenRouter ID |
z-ai/glm-5.1
|
| Provider | z-ai |
| Release Date | April 7, 2026 |
| Context Length | 202,752 tokens |
| Max Completion | 128,000 tokens |
| Status | Active |
Pricing
| Token Type | Cost per 1M tokens | Cost per 1K tokens |
|---|---|---|
| Input | $0.97 | $0.000966 |
| Output | $3.04 | $0.003036 |
Live Performance
Live endpoint metrics, refreshed every 30 minutes.
Leaderboard Categories
External Resources
Frequently asked questions about Z.ai: GLM 5.1
How much does Z.ai: GLM 5.1 cost?
Z.ai: GLM 5.1 costs $0.97 per million input tokens and $3.04 per million output tokens.
What is the context window of Z.ai: GLM 5.1?
Z.ai: GLM 5.1 has a context window of 202,752 tokens (203K).
Is Z.ai: GLM 5.1 good for coding?
On our coding benchmark index, Z.ai: GLM 5.1 ranks #29 of 152 models, placing it in the top quartile of the field for code generation and debugging.
What can Z.ai: GLM 5.1 do?
Z.ai: GLM 5.1 supports tool use and function calling.
Who created Z.ai: GLM 5.1?
Z.ai: GLM 5.1 is developed by Z.ai and was released on April 7, 2026.
